Author name code: ruzmaikin ADS astronomy entries on 2022-09-14 author:"Ruzmaikin, Alexander" ------------------------------------------------------------------------ Title: Clustering of Fast Coronal Mass Ejections during Solar Cycles 23 and 24 and Implications for CME-CME Interactions Authors: Rodriguez Gomez, Jenny Marcela; Podlachikova, Tatiana; Veronig, Astrid; Ruzmaikin, Alexander; Feynman, Joan; Petrukovich, Anatoly Bibcode: 2021EGUGA..23.3990R Altcode: Coronal Mass Ejections (CMEs) and their interplanetary counterparts (ICMEs) are the major sources for strong space weather disturbances. We present a study of statistical properties of fast CMEs (v≥1000 km/s) that occurred during solar cycles 23 and 24. We apply the Max Spectrum and the declustering threshold time methods. The Max Spectrum can detect the predominant clusters, and the declustering threshold time method provides details on the typical clustering properties and timescales. Our analysis shows that during the different phases of solar cycles 23 and 24, fast CMEs preferentially occur as isolated events and in clusters with, on average, two members. However, clusters with more members appear, particularly during the maximum phases of the solar cycles. During different solar cycle phases, the typical declustering timescales of fast CMEs are τc =28-32 hrs, irrespective of the very different occurrence frequencies of CMEs during a solar minimum and maximum. These findings suggest that τc for extreme events may reflect the characteristic energy build-up time for large flare and CME-prolific active regions. Statistically associating the clustering properties of fast CMEs with the disturbance storm time index at Earth suggests that fast CMEs occurring in clusters tend to produce larger geomagnetic storms than isolated fast CMEs. Our results highlight the importance of CME-CME interaction and their impact on Space Weather. Title: Clustering of Fast Coronal Mass Ejections during Solar Cycles 23 and 24 and the Implications for CME-CME Interactions Authors: Rodríguez Gómez, Jenny M.; Podladchikova, Tatiana; Veronig, Astrid; Ruzmaikin, Alexander; Feynman, Joan; Petrukovich, Anatoly Bibcode: 2020ApJ...899...47R Altcode: 2020arXiv200610404R We study the clustering properties of fast coronal mass ejections (CMEs) that occurred during solar cycles 23 and 24. We apply two methods: the Max Spectrum method can detect the predominant clusters, and the declustering threshold time method provides details on the typical clustering properties and timescales. Our analysis shows that during the different phases of solar cycles 23 and 24, CMEs with speeds ≥1000 km s-1 preferentially occur as isolated events and in clusters with, on average, two members. However, clusters with more members appear, particularly during the maximum phases of the solar cycles. Over the total period and in the maximum phases of solar cycles 23 and 24, about 50% are isolated events, 18% (12%) occur in clusters with two (three) members, and another 20% in larger clusters ≥4, whereas in a solar minimum, fast CMEs tend to occur more frequently as isolated events (62%). During different solar cycle phases, the typical declustering timescales of fast CMEs are τc = 28-32 hr, irrespective of the very different occurrence frequencies of CMEs during a solar minimum and maximum. These findings suggest that τc for extreme events may reflect the characteristic energy build-up time for large flare and CME-prolific active regions. Statistically associating the clustering properties of fast CMEs with the disturbance storm time index at Earth suggests that fast CMEs occurring in clusters tend to produce larger geomagnetic storms than isolated fast CMEs. This may be related to CME-CME interaction producing a more complex and stronger interaction with Earth's magnetosphere. Title: Nonlinear mean-field dynamo and prediction of solar activity Authors: Safiullin, N.; Kleeorin, N.; Porshnev, S.; Rogachevskii, I.; Ruzmaikin, A. Bibcode: 2018JPlPh..84c7306S Altcode: 2017arXiv171207501S We apply a nonlinear mean-field dynamo model which includes a budget equation for the dynamics of Wolf numbers to predict solar activity. This dynamo model takes into account the algebraic and dynamic nonlinearities of the α effect, where the equation for the dynamic nonlinearity is derived from the conservation law for the magnetic helicity. The budget equation for the evolution of the Wolf number is based on a formation mechanism of sunspots related to the negative effective magnetic pressure instability. This instability redistributes the magnetic flux produced by the mean-field dynamo. To predict solar activity on the time scale of one month we use a method based on a combination of the numerical solution of the nonlinear mean-field dynamo equations and the artificial neural network. A comparison of the results of the prediction of the solar activity with the observed Wolf numbers demonstrates a good agreement between the forecast and observations. Title: Solar cycle variations in mesospheric carbon monoxide Authors: Lee, Jae N.; Wu, Dong L.; Ruzmaikin, Alexander; Fontenla, Juan Bibcode: 2018JASTP.170...21L Altcode: As an extension of Lee et al. (2013), solar cycle variation of carbon monoxide (CO) is analyzed with MLS observation, which covers more than thirteen years (2004-2017) including maximum of solar cycle 24. Being produced primarily by the carbon dioxide (CO2) photolysis in the lower thermosphere, the variations of the mesospheric CO concentration are largely driven by the solar cycle modulated ultraviolet (UV) variation. This solar signal extends down to the lower altitudes by the dynamical descent in the winter polar vortex, showing a time lag that is consistent with the average descent velocity. To characterize a global distribution of the solar impact, MLS CO is correlated with the SORCE measured total solar irradiance (TSI) and UV. As high as 0.8 in most of the polar mesosphere, the linear correlation coefficients between CO and UV/TSI are more robust than those found in the previous work. The photochemical contribution explains most (68%) of the total variance of CO while the dynamical contribution accounts for 21% of the total variance at upper mesosphere. The photochemistry driven CO anomaly signal is extended in the tropics by vertical mixing. The solar cycle signal in CO is further examined with the Whole Atmosphere Community Climate Model (WACCM) 3.5 simulation by implementing two different modeled Spectral Solar Irradiances (SSIs): SRPM 2012 and NRLSSI. The model simulations underestimate the mean CO amount and solar cycle variations of CO, by a factor of 3, compared to those obtained from MLS observation. Different inputs of the solar spectrum have small impacts on CO variation. Title: Solar Cycle Variations as Observed by MLS Carbon Monoxide Authors: Lee, J. N.; Wu, D. L.; Ruzmaikin, A.; Fontenla, J. M. Bibcode: 2017AGUFMSH43B2813L Altcode: More than thirteen years (2004-2017) of carbon monoxide (CO) measurements from the Aura Microwave Limb Sounder (MLS) are analyzed to better understand impacts of solar cycle 24. The upper mesospheric CO, produced primarily by the carbon dioxide (CO2) photolysis in the lower thermosphere, is sensitive to solar irradiance variability. We find that interannual variations of the mesospheric CO concentration are largely driven by the solar-cycle modulated ultraviolet (UV) variation in most of the UV wavelengths (120 to 280 nm) in high latitude regions. Despite different mean CO abundances in the SH and NH winters, their solar-cycle dependence appears to be symmetric with respect to the winter pole. This solar signal extends down to the lower altitudes by the dynamical descent in the polar vortex, showing a time lag that is consistent with the average descent velocity. To characterize a global distribution of the solar influence, Aura MLS CO is correlated with the Solar Radiation and Climate Experiment (SORCE) Total Irradiance Monitor (TIM) measured total solar irradiance (TSI) and with the SORCE Solar-Stellar Irradiance Comparison Experiment (SOLSTICE) measured UV. As high as 0.8 in most of the polar mesosphere, the linear correlation coefficients between CO and UV/TSI are more robust than those found in the previous work, with the extended analysis period. Different from the result shown in Lee et al. (2013), the downward propagation of the solar signals is similar in both NH and SH high latitudes. Effects of solar forcing on mesospheric CO extend far beyond the polar region. CO is a good tracer to show that the solar induced CO anomaly seems to follow the global meridional residual circulation and hemispheric transition from pole to pole in every six months. WACCM simulation experiment with two different solar spectral irradiance models, SRPM (Solar Radiation Physical Modeling) 2012 and NRLSSI (Naval Research Laboratory Spectral Solar Irradiance), shows that the modeled CO variability in the mesosphere over a solar cycle is weaker by a factor of three than that shown from MLS CO observation. Two different model inputs for the solar spectrum have small impacts, not enough to explain the large discrepancy with the observation. Lacks of strength and variability of the mean meridional circulation in the model, instead of the model photochemistry, most likely cause the weak CO variability in the mesosphere. Title: The Earth's Climate at Minima of the Centennial Gleissberg Cycles Authors: Ruzmaikin, A.; Feynman, J. Bibcode: 2016AGUFMSH43D2593R Altcode: The recent extended and deep minimum of solar variability and the extended minima in the 19th and 20th centuries (1810-1830 and 1900-1920) are consistent with minima of the Centennial Gleissberg Cycle (CGC), a 90-100 year variation of the amplitude of the 11-year sunspot cycle observed on the Sun, solar wind, and at the Earth. The CGC has been identified in the Total Solar Irradiance reconstructed for over three centuries. The Earth's climate response to the prolonged low solar irradiance involves heat transfer to the deep ocean with a time lag longer than a decade. The CGC minima, sometimes coincidently in combination with volcanic forcing, are associated with severe weather extremes. Thus the 19th century CGC minimum, coexisted with volcanic eruptions, led to especially cold conditions in United States, Canada and Western Europe ("a year without summer"). Using the reconstructed solar forcing and modeled and reconstructed Earth's temperature data we identify the timing and spatial pattern of the Earth's climate response that allows distinguishing the solar forcing from other climate forcings. Title: The Earth's climate at minima of Centennial Gleissberg Cycles Authors: Ruzmaikin, Alexander; Feynman, Joan Bibcode: 2015AdSpR..56.1590R Altcode: The recent extended, deep minimum of solar variability and the extended minima in the 19th and 20th centuries (1810-1830 and 1900-1920) are consistent with minima of the Centennial Gleissberg Cycle (CGC), a 90-100 year variation of the amplitude of the 11-year sunspot cycle observed on the Sun and at the Earth. The Earth's climate response to these prolonged low solar radiation inputs involves heat transfer to the deep ocean causing a time lag longer than a decade. The spatial pattern of the climate response, which allows distinguishing the CGC forcing from other climate forcings, is dominated by the Pacific North American pattern (PNA). The CGC minima, sometimes coincidently in combination with volcanic forcing, are associated with severe weather extremes. Thus the 19th century CGC minimum, coexisted with volcanic eruptions, led to especially cold conditions in United States, Canada and Western Europe. Title: Clustering of atmospheric data by the deterministic annealing Authors: Ruzmaikin, Alexander; Guillaume, Alexandre Bibcode: 2014JASTP.120..121R Altcode: The Deterministic Annealing (DA) clustering method, which determines the cluster centers, their sizes, and probability with which data are associated with each cluster, is tested using artificial data and applied to atmospheric satellite data. It is also shown how the method can be advantageously used to characterize data outliers. The method is based on the optimization of a cost function that depends both on the averaged distance of data points to cluster centers and the Shannon entropy of the data. The cost function uses two independent parameters in a close analog to the Gibbs' thermodynamics (with the averaged distance similar to the internal energy) allowing a sufficient control of the formation of new clusters as “phase transitions” by changing the clustering parameter similar to the thermodynamical temperature. The satellite data used are a temperature-water vapor data set and the positions of deep convective clouds obtained from the measurements of the Atmospheric InfraRed Sounder (AIRS) on the Aqua satellite. The clustering of these data is demonstrated for the 2D case (at fixed pressure level) and for the 3D case at multiple pressure levels indicating potential applications to investigation of distributions of atmospheric profiles. Title: The Centennial Gleissberg Cycle and its association with extended minima Authors: Feynman, J.; Ruzmaikin, A. Bibcode: 2014JGRA..119.6027F Altcode: The recent extended minimum of solar and geomagnetic variability (XSM) mirrors the XSMs in the nineteenth and twentieth centuries: 1810-1830 and 1900-1910. Such extended minima also were evident in aurorae reported from 450 A.D. to 1450 A.D. This paper argues that these minima are consistent with minima of the Centennial Gleissberg Cycles (CGCs), a 90-100 year variation observed on the Sun, in the solar wind, at the Earth, and throughout the heliosphere. The occurrence of the recent XSM is consistent with the existence of the CGC as a quasiperiodic variation of the solar dynamo. Evidence of CGCs is provided by the multicentury sunspot record, by the almost 150 year record of indexes of geomagnetic activity (1868 to present), by 1000 years of observations of aurorae (from 450 to 1450 A.D.) and millennial records of radionuclides in ice cores. The aa index of geomagnetic activity carries information about the two components of the solar magnetic field (toroidal and poloidal), one driven by flares and coronal mass ejections (related to the toroidal field) and the other driven by corotating interaction regions in the solar wind (related to the poloidal field). These two components systematically vary in their intensity and relative phase giving us information about centennial changes of the sources of solar dynamo during the recent CGC over the last century. The dipole and quadrupole modes of the solar magnetic field changed in relative amplitude and phase; the quadrupole mode became more important as the XSM was approached. Some implications for the solar dynamo theory are discussed. Title: Patterns of carbon monoxide in the middle atmosphere and effects of solar variability Authors: Ruzmaikin, Alexander; Lee, Jae N.; Wu, Dong L. Bibcode: 2014AdSpR..54..320R Altcode: We determine the spatial-time patterns of zonally averaged carbon monoxide (CO) in the middle atmosphere by applying Principle Component Analysis to the CO data obtained from the Microwave Limb Sounder (MLS) measurements on the Aura satellite in 2004-2012. The first two principal components characterize more than 90% of the CO variability. Both principal components are localized in the low thermosphere near the mesopause. The first principal component is asymmetric relative to the poles. It has opposite signs in the Northern and Southern Hemisphere at mid to high latitudes and strongly oscillates with an annual periodicity. The second principal component has the same sign in both hemispheres and oscillates mainly with a semi-annual frequency. Both principal components are modulated by the 11-year solar cycle and display short-term variations. To test possible correlations of these variations with the short term solar ultraviolet (UV) variability we use the simultaneous measurements of the UV solar radiance from the Solar-Stellar Irradiance Comparison Experiment (SOLSTICE) on the Solar Radiation and Climate Experiment (SORCE) satellite to investigate the correlation between CO in the middle atmosphere and solar UV in 2004-2012. Using a wavelet coherence technique a weak, intermittent 27-day signal is detected in high-frequency parts of the CO principal components. Title: The Centennial Gleissberg Cycle: Origin and Forcing of Climate Authors: Ruzmaikin, A.; Feynman, J. Bibcode: 2014ASPC..484..189R Altcode: We discuss the origin of the Centennial Gleissberg Cycle (CGC) of solar activity and its forcing of the Earth's climate. The solar dynamo models, which explain the process of generating the 11-year cycle via the differential rotation and mean helicity, need to be extended to a non-linear regime that includes feedback processes. The strongest feedback on the centennial time scale is expected from the mean helicity. We advocate that the best way to see the response of the Earth's climate to the CGC forcing is to investigate the climate patterns, not the global temperature. There is anecdotal evidence of extreme low temperatures in the climate patterns at the GCC minima. Numerical modeling indicates a patterned response of the ocean to the CGC forcing. Title: Minima of the Centennial Gleissberg Cycle and the Heliospheric Boundary Authors: Feynman, J.; Ruzmaikin, A. Bibcode: 2014ASPC..484...36F Altcode: The Centennial Gleissberg Cycle (CGC) is a 90-100 year variation observed on the Sun, in the solar wind, at Earth and throughout the Heliosphere. The CGC is expressed as a systematic variation of the amplitude of the 11-year sunspot cycle. The reality of the CGC was a matter of some debate, but the very weak solar wind that occurred during the recent transition from solar cycle 23 to 24 followed by a low cycle 24 maximum sunspot number, strongly supports the concept. In this paper we demonstrate the strong similarities among the CGC minima observed at the beginnings of the 18th, 19th, 20th, and 21st century. These similarities support the notion that we are now experiencing a typical CGC minimum solar wind that is significantly different from the solar wind observed earlier in the space age. We suggest that the current CGC minimum may be implicated in producing some aspects of the unexpected observations at the heliosphere boundary reported at this conference. Title: Solar Variability on Centennial Time Scale Authors: Ruzmaikin, Alexander Bibcode: 2014cosp...40E2819R Altcode: The recent extended minimum of solar variability mirrors the minima in the 20th, 19th, 18th and earlier centuries. These minima fit into the Centennial Gleissberg Cycle (CGC), a 90-100 year variation observed on the Sun, in the solar wind, at the Earth and throughout the Heliosphere. Evidence of the CGC is provided by the multi-century sunspot record, and by longer records of the geomagnetic activity and radio nuclear isotopes. To explain the centennial solar variability in the framework of the mean-field solar dynamo the back action of the mean magnetic field on the sources of its generation must be taken into account. There is observational evidence of extreme low Earth’s temperatures at the GCC minima indicating the CGC variability influence on climate. A good way to see the response of the Earth's climate to the CGC forcing is to investigate the climate patterns. Title: Interannual variations of MLS carbon monoxide induced by solar cycle Authors: Lee, Jae N.; Wu, Dong L.; Ruzmaikin, Alexander Bibcode: 2013JASTP.102...99L Altcode: More than eight years (2004-2012) of carbon monoxide (CO) measurements from the Aura Microwave Limb Sounder (MLS) are analyzed. The mesospheric CO, largely produced by the carbon dioxide (CO2) photolysis in the lower thermosphere, is sensitive to the solar irradiance variability. The long-term variation of observed mesospheric MLS CO concentrations at high latitudes is likely driven by the solar-cycle modulated UV forcing. Despite of different CO abundances in the southern and northern hemispheric winter, the solar-cycle dependence appears to be similar. This solar signal is further carried down to the lower altitudes by the dynamical descent in the winter polar vortex. Aura MLS CO is compared with the Solar Radiation and Climate Experiment (SORCE) total solar irradiance (TSI) and also with the spectral irradiance in the far ultraviolet (FUV) region from the SORCE Solar-Stellar Irradiance Comparison Experiment (SOLSTICE). Significant positive correlation (up to 0.6) is found between CO and FUV/TSI in a large part of the upper atmosphere. The distribution of this positive correlation in the mesosphere is consistent with the expectation of CO changes induced by the solar irradiance variations. Title: Decadal variability of tropical Pacific temperature in relation to solar cycles Authors: Ruzmaikin, Alexander; Aumann, Hartmut H. Bibcode: 2012AdSpR..49..572R Altcode: We use the 8-year long satellite temperature data (2002-2010) from Atmospheric InfraRed Sounder (AIRS) and Atmospheric Microwave Sounding Unit (AMSU) on the Aqua satellite to identify temperature trends in the troposphere and low stratosphere over the Niño 3.4 region of the Tropical Pacific Ocean in the most recent 11-year solar cycle. Employing more extended sea surface temperature (SST) data for five solar cycles (1950-2009) in this region we show that the satellite trends reflect a typical decrease of the sea surface temperature (SST) in the Niño 3.4 region in the declining phase of the solar cycle. The magnitude of the SST decrease depends on the solar cycle and ranges between 0.07 K/yr and 0.27 K/yr for the last five solar cycles. Title: Implications of the Deep Cycle 23/24 Minimum for our Understanding of the Solar Dynamo Authors: Feynman, J.; Ruzmaikin, A. Bibcode: 2011AGUFMSH24B..03F Altcode: When the cycle 23/24 minimum is considered in the light of the existing record of 1,500 years of solar output proxies, it can be understood as a typical minimum of a periodic modulation of the amplitude of the 11-year solar cycle, which we call the Centennial Gleissberg Cycle (CGC). This 90-100 year amplitude variation has been well established by earlier studies (Gleissberg, 1965, Siscoe, 1980, Silverman and Feynman, 1980, Sonnett, 1982) and is present at least 80% of the time since 450 AD. It consists of a series of about nine or ten 11-year cycles with amplitudes that gradually rise and then fall (Feynman and Fougere, 1988). Previous well-established deep minima took place about 1710, 1810 (Dalton Minimum) and 1910. Because of this record a minimum about 2010 was not unexpected (e.g. Silverman, 1992). The CGC was also seen in auroral observations from 450 AD to 1450 AD. It thus appears that the magnetic field generated by the solar dynamo has a quasi-periodic variation of about 100 years, the cause of which demands future study. In this talk we will review the evidence that the peculiar behavior noticed during 23/24 minimum was a CGC minimum. We will describe the CGC and develop criteria to distinguish it from Grand Minima such as the Maunder Minimum. When these criteria are applied to the observations, the CGC hypothesis is clearly favored. We will discuss possible models of non-linear dynamos that can explain the origin of the CGC. Title: The Sun's Strange Behavior: Maunder Minimum or Gleissberg Cycle? Authors: Feynman, J.; Ruzmaikin, A. Bibcode: 2011SoPh..272..351F Altcode: During the last few years the Sun and solar wind have shown a behavior that was so unexpected that the phenomena was described as "the strange solar minimum". It has been speculated that the 23/24 solar cycle minimum may have indicated the onset of a Maunder-Minimum-type Grand Minimum. Here we review what is known from 1500 years of proxy data about Maunder-type Grand Minima and the minima of the cyclic Centennial Gleissberg variations. We generate criteria that distinguish between the two types of event. Applying these criteria to the observed solar terrestrial data we conclude that the unexpected behavior began well before the solar cycle 23/24 minimum. The data do not support the Maunder Minimum conjecture. However, the behavior can be understood as a minimum of the Centennial Gleissberg Cycle that previously minimized in the beginning of the 20th century. We conclude that the Centennial Gleissberg Cycle is a persistent variation that has been present 80% of the time during the last 1500 years and should be explained by solar dynamo theory. Title: Distribution and clustering of fast coronal mass ejections Authors: Ruzmaikin, A.; Feynman, J.; Stoev, S. A. Bibcode: 2011JGRA..116.4220R Altcode: The purpose of this paper is to investigate the statistical properties of high-speed coronal mass ejections (fast CMEs), which play a major role in Space Weather. We study the cumulative distribution of the initial CME speeds applying a new, advanced statistical method based on the scaling properties of averages of maximal speeds selected in time intervals of fixed sizes. This method allows us for the first time to obtain a systematic statistical description of the fast CME speeds. Using this method, we identify a self-similar (power law) high-speed portion of the spectrum of the speed maxima in the range of speeds from about 700 km/s to 2000 km/s. This self-similar range of the speed distribution provides a meaningful definition of “the fast” CMEs and indicates that these CMEs are produced by a process that is the same across the range of scales. The investigation of the temporal behavior of the fast CME events indicates that the time intervals between fast CMEs are not independent, i.e., fast CMEs arrive in clusters. We characterize the fast CMEs clustering by the exponent $\theta$ called the extremal index, which is the inverse of the averaged number of CMEs per cluster. An independent correlation analysis of the tail of the CME distribution confirms and further quantifies the temporal dependence among the fast CME events. To illustrate the predictive capabilities of the method, we identify clusters in the time series of CMEs with speeds greater than 1000 km/s and calculate their statistical characteristics such as the size and duration of the clusters. The method used in this paper can be applied to many other extreme geophysical events. Title: Distribution of extreme solar energetic proton fluxes Authors: Ruzmaikin, Alexander; Feynman, Joan; Jun, Insoo Bibcode: 2011JASTP..73..300R Altcode: The knowledge of the high intensity tails of probability distributions that determine the rate of occurrence of extreme events of solar energetic particles is a critical element in the evaluation of hazards for human and robotic space missions. Here instead of the standard approach based on fitting a selected distribution function to the observed data we investigate a different approach, which is based on a study of the scaling properties of the maximum particle flux in time intervals of increasing length. To find the tail of the probability distributions we apply the “Max-Spectrum” method (Stoev, S.A., Michailidis, G., 2006. On the estimation of the heavy-tail exponent in time series using the Max-Spectrum. Technical Report 447, Department of Statistics, University of Michigan) to 1973-1997 IMP-8 proton data and the 1987-2008 GOES data, which cover a wide range of proton energies. We find that both data sets indicate a power-law tail with the power exponents close to 0.6 at least in the energy range 9-60 MeV. The underlying probability distribution is consistent with the Fréchet type (power-law behavior) extreme value distribution. Since the production of high fluxes of energetic particles is caused by fast Coronal Mass Ejections (CMEs) this heavy-tailed distribution also means that the Sun generates more fast CMEs than would be expected from a Poissonian-type process. Title: Distribution and Clustering of Fast Coronal Mass Ejections Authors: Feynman, J.; Ruzmaikin, A.; Stoev, S. Bibcode: 2010AGUFMSH43A1809F Altcode: In many geophysical phenomena such as hurricanes, the solar energetic particle events and the coronal mass ejections we discuss here, the knowledge of the tails of the probability distribution functions is critical to our understanding and forecasting of the most hazardous extreme events. In addition, often the events appear to cluster making †he statistical samplings based on independent events incorrect. The probability distributions of extreme events are not Gaussian but are characterized by extended high intensity tails. In practice, it has become common to estimate the shape of the tail using an empirical fit to a known distribution function, such as a log-normal. These empirical estimates are often challenged because the validity of the basic mathematics of statistics underlying them has not been demonstrated. Recently new statistical techniques have been developed that allow us to test the validity of our empirical methods. We apply one of the new methods based on the use of scaling properties of the data maxima to the distribution of speeds of coronal mass ejections (CMEs). We show that the distribution function of the fast CME speeds asymptotically follows the power-law extreme value distribution and that the intervals between fast CMEs do not follow the exponential distribution expected for independent random events but cluster in time. This work was supported by the Jet Propulsion Laboratory of the California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Title: The DynaMICCS perspective. A mission for a complete and continuous view of the Sun dedicated to magnetism, space weather and space climate Authors: Turck-Chièze, S.; Lamy, P.; Carr, C.; Carton, P. H.; Chevalier, A.; Dandouras, I.; Defise, J. M.; Dewitte, S.; Dudok de Wit, T.; Halain, J. P.; Hasan, S.; Hochedez, J. F.; Horbury, T.; Levacher, P.; Meissonier, M.; Murphy, N.; Rochus, P.; Ruzmaikin, A.; Schmutz, W.; Thuillier, G.; Vivès, S. Bibcode: 2009ExA....23.1017T Altcode: 2008ExA...tmp...42T The DynaMICCS mission is designed to probe and understand the dynamics of crucial regions of the Sun that determine solar variability, including the previously unexplored inner core, the radiative/convective zone interface layers, the photosphere/chromosphere layers and the low corona. The mission delivers data and knowledge that no other known mission provides for understanding space weather and space climate and for advancing stellar physics (internal dynamics) and fundamental physics (neutrino properties, atomic physics, gravitational moments...). The science objectives are achieved using Doppler and magnetic measurements of the solar surface, helioseismic and coronographic measurements, solar irradiance at different wavelengths and in-situ measurements of plasma/energetic particles/magnetic fields. The DynaMICCS payload uses an original concept studied by Thalès Alenia Space in the framework of the CNES call for formation flying missions: an external occultation of the solar light is obtained by putting an occulter spacecraft 150 m (or more) in front of a second spacecraft. The occulter spacecraft, a LEO platform of the mini sat class, e.g. PROTEUS, type carries the helioseismic and irradiance instruments and the formation flying technologies. The latter spacecraft of the same type carries a visible and infrared coronagraph for a unique observation of the solar corona and instrumentation for the study of the solar wind and imagers. This mission must guarantee long (one 11-year solar cycle) and continuous observations (duty cycle > 94%) of signals that can be very weak (the gravity mode detection supposes the measurement of velocity smaller than 1 mm/s). This assumes no interruption in observation and very stable thermal conditions. The preferred orbit therefore is the L1 orbit, which fits these requirements very well and is also an attractive environment for the spacecraft due to its low radiation and low perturbation (solar pressure) environment. This mission is secured by instrumental R and D activities during the present and coming years. Some prototypes of different instruments are already built (GOLFNG, SDM) and the performances will be checked before launch on the ground or in space through planned missions of CNES and PROBA ESA missions (PICARD, LYRA, maybe ASPIICS). Title: Quasi-periodic patterns coupling the Sun, solar wind and the Earth Authors: Ruzmaikin, Alexander; Cadavid, Ana Cristina; Lawrence, John Bibcode: 2008JASTP..70.2112R Altcode: The spectrum of velocity and magnetic fields in the solar wind is self-similar (power-law type) in the frequency range greater than >1/day indicating well-mixed turbulence. But it loses self-similarity for lower frequencies indicating the presence of large-scale patterns, which are intermittently generated inside the Sun and propagate from the Sun to the Earth. Here we discuss the spatia-temporal characteristics and origin of the 1.3-year quasi-periodic pattern found inside the Sun by helioseismic methods and detected in the solar wind. To identify and characterize this pattern on the Sun we use time series of solar magnetic Carrington maps generated at the Wilcox Solar Observatory and independent component data analysis. This analysis shows the latitudinal distribution of the pattern, its variable frequency and intermittent appearance. Title: Frequency of severe storms and global warming Authors: Aumann, Hartmut H.; Ruzmaikin, Alexander; Teixeira, Joao Bibcode: 2008GeoRL..3519805A Altcode: We use five years of data from the Atmospheric Infrared Sounder (AIRS) to develop a correlation between the frequency of Deep Convective Clouds (DCC) and the zonal mean tropical surface temperature. AIRS data show that the frequency of DCC in the tropical oceans is very temperature sensitive, increasing 45% per 1 K increase of the zonal mean surface temperature. The combination of the sensitivity of the DCC frequency to temperature indicates that the frequency of DCC, and as a consequence the frequency of severe storms, increases at the rate of 6%/decade with the current +0.13 K/decade rate of global warming. This result is only qualitatively consistent with state-of-the-art climate models, where the frequency of the most intense rain events increases with global warming. Title: Rotational Quasi-Periodicities and the Sun - Heliosphere Connection Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. Bibcode: 2008SoPh..252..179L Altcode: 2008arXiv0803.3260L; 2008SoPh..tmp..138L Mutual quasi-periodicities near the solar-rotation period appear in time series based on the Earth's magnetic field, the interplanetary magnetic field, and signed solar-magnetic fields. Dominant among these is one at 27.03±0.02 days that has been highlighted by Neugebauer et al. (J. Geophys. Res.105, 2315, 2000). Extension of their study in time and to different data reveals decadal epochs during which the ≈ 27.0 days, or a ≈ 28.3 days, or other quasi-periods dominate the signal. Space-time eigenvalue analyses of time series in 30 solar latitude bands, based on synoptic maps of unsigned photospheric fields, lead to two maximally independent modes that account for almost 30% of the data variance. One mode spans 45° of latitude in the northern hemisphere and the other one in the southern. The modes rotate around the Sun rigidly, not differentially, suggesting connection with the subsurface dynamo. Spectral analyses yield familiar dominant quasi-periods 27.04±0.03 days in the North and at 28.24±0.03 days in the South. These are replaced during cycle 23 by one at 26.45±0.03 days in the North. The modes show no tendency for preferred longitudes separated by ≈ 180°. Title: Principal Components and Independent Component Analysis of Solar and Space Data Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. Bibcode: 2008SoPh..248..247C Altcode: 2007arXiv0709.3263C Principal components analysis (PCA) and independent component analysis (ICA) are used to identify global patterns in solar and space data. PCA seeks orthogonal modes of the two-point correlation matrix constructed from a data set. It permits the identification of structures that remain coherent and correlated or that recur throughout a time series. ICA seeks for maximally independent modes and takes into account all order correlations of the data. We apply PCA to the interplanetary magnetic field polarity near 1 AU and to the 3.25R⊙ source-surface fields in the solar corona. The rotations of the two-sector structures of these systems vary together to high accuracy during the active interval of solar cycle 23. We then use PCA and ICA to hunt for preferred longitudes in northern hemisphere Carrington maps of magnetic fields. Title: Search for Persistent Quasi-Periodicities in the Solar and Interplanetary Magnetic Fields Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. Bibcode: 2007AGUFMSH23A1165L Altcode: Previous analysis of the radial component of the interplanetary magnetic field from 1962 - 1998 has revealed a dominant frequency of 27.03 days to 0.02 day accuracy (Neugebauer, et al., 2000). We have repeated and extended this analysis with OMNI data from 1963 - 2007 obtained from the Coordinated Heliospheric Observations (COHO) database. Over this longer data string we find that the 27.03 day Lomb-Scargle periodogram peak is reduced while two side peaks near 26.8 days and 27.6 days become almost as strong. In the interval 1999-2007 there are two dominant periods near 26.5 days and 27.2 days. As a solar counterpart to the above analysis we have searched for persistent rotation periods near 27 days of global patterns of photospheric magnetic fields derived from Wilcox Solar Observatory synoptic Carrington rotation maps. Techniques applied include, principal components analysis, independent component analysis, singular spectrum analysis, wavelet spectral analysis, and complex demodulation. We find a variety of quasi- periodicities between 26 and 29 days that remain coherent for 1 - 2 years. In the southern solar hemisphere the strongest periodicity is at 28.2 days, while in the northern hemisphere it is around 26.5 days. Neugebauer, M., Smith, Smith, E.J., Ruzmaikin, A., Feynman, J., Vaughan, A.H. 2000, J. Geophys. Res., 106, A5, 8363. Title: Sunspots, El Niño, and the levels of Lake Victoria, East Africa Authors: Stager, J. Curt; Ruzmaikin, Alexander; Conway, Declan; Verburg, Piet; Mason, Peter J. Bibcode: 2007JGRD..11215106S Altcode: An association of high sunspot numbers with rises in the level of Lake Victoria, East Africa, has been the focus of many investigations and vigorous debate during the last century. In this paper, we show that peaks in the ~11-year sunspot cycle were accompanied by Victoria level maxima throughout the 20th century, due to the occurrence of positive rainfall anomalies ~1 year before solar maxima. Similar patterns also occurred in at least five other East African lakes, which indicates that these sunspot-rainfall relationships were broadly regional in scale. Although irradiance fluctuations associated with the sunspot cycle are weak, their effects on tropical rainfall could be amplified through interactions with sea surface temperatures and atmospheric circulation systems, including ENSO. If this Sun-rainfall relationship persists in the future, then sunspot cycles can be used for long-term prediction of precipitation anomalies and associated outbreaks of insect-borne disease in much of East Africa. In that case, unusually wet rainy seasons and Rift Valley Fever epidemics should occur a year or so before the next solar maximum, which is expected to occur in 2011-2012 AD. Title: Impact of Solar Variability on the Earth's Climate Patterns Authors: Ruzmaikin, A. Bibcode: 2007AGUSM.A52B..02R Altcode: We discuss the effect of solar variability on the Earth climate patterns. The climate patterns are naturally excited in the noisy atmosphere-ocean dynamical system as deviations (anomalies) from a global (mean) state. Some of the climate patterns couple the upper and lower atmosphere and are affected by the ocean. An example of this type of climate pattern is the Northern Annular Mode (NAM), a climate anomaly with two basic states corresponding to higher pressure at high latitudes with a band of lower pressure at lower latitudes and the other way round (Thompson & Wallace, 1998; Baldwin & Dunkerton, 1999). Two states of the NAM arise due to the dynamical interaction of planetary waves and zonal mean wind (Limpasuvan & Hartmann, 2001; Ruzmaikin et al., 2006). The NAM accounts for 23% of atmospheric variability at sea level and about 50% of the variability in the stratosphere. Solar variability influences the NAM through the change of the UV flux in upper atmosphere. The influence depends on the phase of the Quasi Biennial Oscillation and time in the winter season (Ruzmaikin & Feynman, 2002). We discuss a possible mechanism by which solar variability can affect the NAM and the climate patterns in general (involving the Rossby-Palmer conjecture, Palmer, 1999). In contrast to the standard linear evaluation of climate sensitivity to an external forcing we outline a non-linear approach to the forcing problem. In particular, we evaluate the distributions of residence times spent in each state of the pattern and show how these distributions depend on external forcing caused by the anthropogenic and solar changes. References: Thompson, D. W. J. & J. M. Wallace, Geophys. Res. Lett., 25, 1297, 1998; Baldwin, M. P. & T. J. Dunkerton, J. Geophys. Res. 104, 30,937, 1999; Limpasuvan, V., & D. Hartmann, J. Climate, 13, 4414, 2001; Ruzmaikin, A., J, Feynman, J. Geophys. Res., 107, D14, 10.1029/2001JD001239, 2002; Ruzmaikin, A., J. K. Lawrence & A. C. Cadavid, J. Atmos. Space Phys., 68, 1311, 2006; Palmer, T. N., Bull. Amer. Meteor. Soc., 79, 1412 1998. Title: Effect of solar variability on the Earth’s climate patterns Authors: Ruzmaikin, Alexander Bibcode: 2007AdSpR..40.1146R Altcode: We discuss effects of solar variability on the Earth's large-scale climate patterns. These patterns are naturally excited as deviations (anomalies) from the mean state of the Earth's atmosphere-ocean system. We consider in detail an example of such a pattern, the North Annular Mode (NAM), a climate anomaly with two states corresponding to higher pressure at high latitudes with a band of lower pressure at lower latitudes and the other way round. We discuss a mechanism by which solar variability can influence this pattern and formulate an updated general conjecture of how external influences on Earth's dynamics can affect climate patterns. Title: The 27-day variations in stratospheric ozone and temperature: New MLS data Authors: Ruzmaikin, A.; Santee, M. L.; Schwartz, M. J.; Froidevaux, L.; Pickett, H. M. Bibcode: 2007GeoRL..34.2819R Altcode: We use new data obtained by the Microwave Limb Sounder (MLS) onboard of Aura spacecraft to investigate variations in stratospheric ozone and temperature concurrent with the 27-day variations of solar UV irradiance, measured simultaneously by the Solar Radiation and Climate Experiment (SORCE) during the declining phase of solar activity. Using Empirical Mode Decomposition we determine the latitudinal and height distributions of the 27-day modes for ozone and temperature and find that these modes are enhanced in the lower tropical stratosphere, and at high latitudes in winter. Title: Statistics of solar energetic particle events: Fluences, durations, and time intervals Authors: Jun, I.; Swimm, R. T.; Ruzmaikin, A.; Feynman, J.; Tylka, A. J.; Dietrich, W. F. Bibcode: 2007AdSpR..40..304J Altcode: The high-energy solar proton data obtained from instruments onboard the IMP-8 spacecraft are used to investigate statistical distributions of event fluences, event durations, and time intervals between adjacent events. The results show that: (1) the event fluences can be approximately fit to a log-normal distribution and (2) the distributions of event durations and time intervals between the events can be represented by Poisson distributions. A virtual data set was generated using these distributions to extend the Solar Probe method [Feynman, J., Tylka, A.J., Reames, D.B., Gabriel, S.B. Near-sun energetic particle environment of Solar Probe-Phase1 final report, JPL Report, 2000] of obtaining the mission-integrated fluences to longer missions. By using the virtual data set generated in this study, we are able to obtain the smooth distribution of mission fluences for missions of any duration, which is not possible when only the available data sets was used. Title: Quasi-Periodicities, Magnetic Clusters and Solar Activity Authors: Cadavid, A. C.; Lawrence, J. K.; Sandor, C.; Ruzmaikin, A. Bibcode: 2006AGUFMSH21A0325C Altcode: To investigate quasi-periodicities, 12 hour averages of the radial component of the interplanetary magnetic field and the solar wind speed, covering ~ 42 (1963-2005) years were analyzed. A Lomb periodogram for data up to 1998 showed a dominant period of 27.03 days as fpund in earlier results. Including cycle 23, a dominant period of 27.06 days was identified. Analysis of the solar cycles independently showed a dominant period of 27.03 days in solar cycle 20, but not in the other cycles. To investigate the degree of persistency of a particular signal, the technique of complex demodulation was applied since it permits the determination of continuous changes in time of the amplitude and frequency of the signal relative to the test signal. It was found that a period of ~27.6 days gave an overall flat phase function in time, while other periods < ~0.5 day shorter and longer, with comparable but lesser amplitude, come and go. To investigate the solar sources of these periods, the method of principal component analysis (PCA) was applied to ~ 27 years (1976-2003) of synoptic maps obtained with the NSO Kitt Peak Vaccum Telescope. Before the analysis, the original synoptic maps were shifted relative to the previous maps using the period under investigation. Using PCA the Empirical Orthogonal Functions (EOFs) and Pricipal Components (PCs) were found for the set of synoptic maps rescaled to the rotation rate 27.03 days in 1999-2003. The patterns characterized by EOFs 1 and 2 are mostly axisymmetric and PCs 1 and 2 show solar cycle variability. EOF3 shows only one well-localized pattern in the Southern Hemisphere which is markedly non-axisymmetric and PC3 has peaks at times when fast CMEs occur. Title: The New JPL Interplanetary Solar High-Energy Particle Environment Model Authors: Jun, I.; Swimm, R. T.; Ruzmaikin, A.; Feynman, J.; Tylka, A. J.; Dietrich, W. F. Bibcode: 2006AGUFMSH51A1468J Altcode: The high-energy protons and heavy ions from solar energetic particle (SEP) events present hazard to space systems: damage to science instruments/electronics or to astronauts. A reliable estimate of the high-energy particle environment is very important to assure the mission success. Without it, system survivability is often ensured by setting grossly over-conservative mission requirements, resulting in high mission costs, weight and physically large systems. However, at present our ability to reliably predict the space environments for missions not shielded by planetary magnetic fields is surprisingly poor, especially for missions not at 1 AU. The primary reasons for this are that: (1) SEP events are infrequent and sporadic, (2) statistically valid data exist only at 1 AU, and (3) radial dependence of SEP fluxes and fluences is still to be determined. Our ultimate goal is to develop an advanced model that can reliably provide statistical estimates of mission- integrated fluences of SEP high-energy protons and heavy ions for arbitrary trajectories, launches on arbitrary future dates, and an improved radial dependence law. This will be achieved by adopting an approach used in a preliminary Solar Probe mission study, that is, by flying a spacecraft through the database (described below) with an appropriate radial dependence law being applied at each time step. Here we present the preliminary results for a high-energy "proton" model. For the study, we use the data obtained from the instruments onboard the IMP-8 spacecraft: Goddard's Low Energy Detector (LED) and Medium Energy Detector (MED) and the University of Chicago's Cosmic Ray Nuclear Composition (CRNC) telescope. The data set covers the period between 1973, day 305, and 1997, day 319, at 1 AU. All the data were averaged over 6- hour intervals and corrected for background by subtracting non-SEP contributions (i.e., contributions from galactic cosmic rays and spurious instrumental effects). Title: Quasi-periodicities and Empirical Modes of the Heliospheric Magnetic Field Authors: Smith, E. J.; Zhou, X.; Ruzmaikin, A. Bibcode: 2006AGUFMSH53B1506S Altcode: Quasi-periodicities in solar phenomena including variations in the heliospheric magnetic field have attracted attention in the past. Recently, such a periodicity near 140- 150 days has been of interest. In a recent analysis of solar cycle variations in the Sun's open magnetic flux, we found a quasi-periodicity of approximately one and one-half years in the radial component and the field magnitude that persists during the last four sunspot cycles. Inspection of the data revealed that this signal was variable in both amplitude and period. Power spectra having proved marginally useful in revealing the signal properties, we apply a new technique called Empirical Mode Decomposition (Huang et al., 1998) that treats both the frequency and amplitude as time-dependent. Application of this technique revealed several quasi-periodic modes including the mode near 1 and 1/2 years and the mode near 140 days that was not evident by inspection alone. The results of this analysis will be presented and the origin of the several periodicities will be discussed. Reference: Huang, N. E. Z. Shen, S. R. Long, M. C. Wu, H. H. Shih, Q. Zheng, N.-C. Yen, C. C. Tung, and H. H. Liu, Proc. R. Soc. Lond., A 454, 903-995, 1998. Title: Effect of Solar Variability on Earth Climate Patterns. Authors: Ruzmaikin, A.; Feynman, J. Bibcode: 2006AGUFMSH11A0357R Altcode: We discuss the impact of solar variability on the patterns of Earth climate variability. These climate patterns are naturally excited in the noisy atmosphere-ocean dynamical system as deviations (anomalies) from a global (mean) state. The patterns include North Atlantic Oscillation (NAO) and related Northern Annular Mode (NAM), Southern Annular Mode (SAM), Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO). An example of a pattern influenced by variations in solar UV irradiance is the NAM, a wintertime climate anomaly with two states corresponding to higher pressure at high latitudes with a band of lower pressure at lower latitudes and the other way round (Thompson &Wallace, 1998). Two states of the NAM arise due to the dynamical interaction of planetary waves and zonal mean wind (Limpasuvan &Hartmann, 2001; Ruzmaikin et al., 2006). The NAM accounts for 23% of atmospheric variability at sea level and about 50% of the variability in the stratosphere. Solar variability affects the NAM and that the influence varies dependent on the phase of the Quasi Biennial Oscillation and time in the winter season (Ruzmaikin &Feynman, 2002). The temperature pattern (cold in Europe-warm in Greenland) produced by the negative NAM was dominant during the Maunder Minimum of solar activity (Ruzmaikin et al., 2004). We discuss possible physical mechanisms by which solar variability can influence the climate patterns. In particular, we address the Rossby-Palmer hypothesis (Palmer, 1998) that external forcing (in our case solar variability) may affect only the magnitude of the pattern variability without changing its spatial structure. References: Thompson, D. W. J. &J. M. Wallace, Geophys. Res. Lett., 25, 1297, 1998; Palmer, T. N., Bull. Amer. Meteor. Soc., 79, 1412 1998; Baldwin, M. P. and T. J. Dunkerton, J. Geophys. Res. 104, 30,937, 1999; Limpasuvan, V., &D. Hartmann, J. Climate, 13, 4414, 2001; Ruzmaikin, A., J, Feynman, J. Geophys. Res., 107, D14, 10.1029/2001JD001239, 2002; Ruzmaikin, A., J, Feynman, Xun Jiang, D. C. Noone, A. M. Waple &Y. L. Yung, Geophys. Res. Let., 31, L12201, 2004; Ruzmaikin, A., J. K. Lawrence &A. C. Cadavid, J. Atmos. Space Phys., 68, 1311, 2006. Title: Stratospheric wave-mean flow interaction: Simple modeling Authors: Ruzmaikin, Alexander; Cristina Cadavid, Ana; Lawrence, John K. Bibcode: 2006JASTP..68.1311R Altcode: 2006JATP...68.1311R We show that the interaction between planetary waves and the stratospheric zonal mean flow results in bi-modal (direct-reverse flow) or unimodal state depending on wave number of the waves. First we demonstrate this using a simple non-linear dynamic system of the wave-flow interaction, which has two stable equilibrium states and one unstable state (attractors) in its phase space. Then we compare this model dynamics with the stratosphere dynamics using the same dynamical variables and a similar parameter range in the National Centers for Environmental Prediction (NCEP) Reanalysis data. This comparison supports the tendency for the states of planetary wave zonal mean flow in the upper stratosphere to be bi-modal for wave number 2 and unimodal for wave number 1. Title: Persistent Peridicities in the Solar Wind and Photospheric Magnetic Field Coherent Structures Authors: Cadavid, Ana C.; Lawrence, J. K.; Ruzmaikin, A. Bibcode: 2006SPD....37.1106C Altcode: 2006BAAS...38..239C To investigate persistent periodicities, 12-hour averages of the radial component of the interplanetary magnetic field and the solar wind speed, covering 42 years (1963-2005), were analyzed. A Lomb periodogram for the data up to 1998 showed maximum spectral power at a period of 27.03 days, as encountered previously by Neugebauer et al. (2000). Including cycle 23 shifted the peak to 27.06 days. Analysis of solar cycles 20 - 23 separately showed a dominant period of 27.03 days in solar cycle 20, but not in the other cycles.To investigate the degree of persistency and phase coherence of a particular signal, the technique of complex demodulation was applied since it permits the determination of continuous changes in time of the amplitude and frequency of the signal relative to a test signal. It was found that for a reference signal of 27.03 days, the phase was a flat function of time during the intervals 1965-1972 and 1995-1997. The phase decreased in time from 1972-1995 and increased after 1997. This implies that for the intervals 1972-1995 and 1997-2005 other periodicities better characterize the data. A period of 27.6 days gave an overall flat phase function in time, while other periods < 0.5 day shorter and longer, with comparable but lesser amplitude, come and go.To investigate the solar sources of these periods, the methods of principal component analysis (PCA) and independent component analysis (ICA) were applied to 27 years (1976-2003) of synoptic maps obtained with the NSO Kitt Peak Vacuum Telescope. Before the analysis, the original synoptic maps were shifted relative to the previous maps using the particular period under investigation. PCA and ICA identified 3 modes for the 27.03 reference period and 2 modes for the 27.6 period that showed clusters of magnetic activity at preferred longitudes. Title: Statistics of solar energetic particle events: fluences, durations, and time intervals Authors: Swimm, R.; Jun, I.; Ruzmaikin, A.; Feynman, J.; Tylka, A. J.; Dietrich, W. F. Bibcode: 2006cosp...36..664S Altcode: 2006cosp.meet..664S The high-energy protons and heavy ions from solar energetic particle SEP events present hazard to space systems damage to science instruments electronics or to astronauts A reliable estimate of the high-energy particle environment is very important to assure the mission success Without it system survivability is often ensured by setting grossly over-conservative mission requirements resulting in high mission costs weight and physically large systems However at present our ability to reliably predict the space environments for missions not shielded by planetary magnetic fields is surprisingly poor especially for missions not at 1 AU The primary reasons for this are that 1 SEP events are infrequent and sporadic 2 statistically valid data exist only at 1 AU and 3 radial dependence of SEP fluxes and fluences is still to be determined Our ultimate goal is to develop an advanced model that can reliably provide statistical estimates of mission-integrated fluences of SEP high-energy protons and heavy ions for arbitrary trajectories launches on arbitrary future dates and an improved radial dependence law This will be achieved by adopting an approach used in a preliminary Solar Probe mission study that is by flying a spacecraft through the database described below with an appropriate radial dependence law being applied at each time step While we are still progressing towards the goal we present here the first results of our study on statistical distributions of event fluences of event durations and of time intervals between adjacent events For Title: Does the Nile reflect solar variability? Authors: Ruzmaikin, Alexander; Feynman, Joan; Yung, Yuk Bibcode: 2006IAUS..233..511R Altcode: Historical records of the Nile water level provide a unique opportunity to investigate the possibility that solar variability influences the Earth's climate. Particularly important are the annual records of the water level, which are uninterrupted for the years 622-1470 A.D. These records are non-stationary, so that standard spectral analyses cannot adequately characterize them. Here the Empirical Mode Decomposition technique, which is designed to deal with non-stationary, nonlinear time series, becomes useful. It allows the identification of two characteristic time scales in the water level data that can be linked to solar variability: the 88 year period and a time scale of about 200 years. These time scales are also present in the concurrent aurora data. Auroras are driven by coronal mass ejections and the rate of auroras is an excellent proxy for solar variabiliy. Analysis of auroral data contemporaneous with the Nile data shows peaks at 88 years and about 200 years. This suggests a physical link between solar variability and the low-frequency variations of the Nile water level. The link involves the influence of solar variability on the North Annual Mode of atmospheric variability and its North Atlantic and Indian Oceans patterns that affect rainfall over Eastren Equatorial Africa where the Nile originates. Title: The radial and longitudinal dependence of SEP intensities and fluences Authors: Li, G.; Zank, G.; Verkhoglyadova, O.; Ruzmaikin, A.; Feynman, J.; Jun, I. Bibcode: 2006cosp...36.3428L Altcode: 2006cosp.meet.3428L Solar Energetic Particles SEPs are an important hazard in the context of space weather These particles bombard spacecraft and can cause instruments onboard to malfunction At sufficiently high energies and dosages they can also be extremely harmful to biological materials human bodies and are therefore one of the major safety concerns for the future manned spacecraft program We now know that these particles are associated with Coronal Mass Ejection CMEs driven shocks As a CME-driven shock propagates outward particles are injected and accelerated at the shock front via a first order Fermi mechanism aka diffusive shock acceleration After being accelerated the particles convect with the shock diffuse both upstream and downstream of the shock and many eventually escape the shock complex after reaching far upstream downstream In this work we present a model calculation of the SEP time intensity profile The model is based on a 2D-ZEUS MHD code which is used to simulate the solar wind The shock is modeled using a shell model where particle convection and diffusion are followed numerically When particles reach some distance ahead of the shock they are can escape from the shock Their subsequent motion is followed using a Monte-Carlo approach This sophisticated model allows us to obtain a time intensity profile and instantaneous particle spectra at various locations We will discuss the radial and longitudinal dependence of both the intensities and fluences Title: Causes of extremely fast CMEs Authors: Feynman, Joan; Ruzmaikin, Alexander Bibcode: 2006IAUS..233..343F Altcode: We study CMEs observed by LASCO to have plane of the sky velocities exceeding 1500 km/sec. We find that these extremely fast CMEs are typically associated with flares accompanied by erupting prominences. Our results are consistent with a single CME initiation process that consists of three stages. The initial stage is brought about by the emergence of new magnetic flux, which interacts with the pre-existing magnetic configuration and results in a slow rise of the magnetic structure. The second stage is a fast reconnection phase with flaring, filament eruption and a sudden increase of the rise velocity of the magnetic structure (CME). The third stage consists of propagation in the corona. We discuss the sources of these CMEs and the need for improved understanding of the first and third stages. Title: Coherent Structures vs Independent Modes of the Axisymmetric Magnetic Field Fluctuations Authors: Cadavid, A. C.; Lawrence, J. K.; McDonald, D. P.; Ruzmaikin, A. Bibcode: 2005ASPC..346...91C Altcode: Quasi periodicities on scales of 1 to 2.5 years have been observed in solar, interplanetary and geomagnetic time series. The relation of these signals to 1 and 1.3 yr fluctuations in the solar interior, suggest the presence of structures or characteristic modes in the magnetic field, generated by the dynamo, that extend into the heliosphere. We have applied the methods of principal component analysis (PCA) and independent component analysis (ICA) to search for the coherent structures (PCA) and independent global modes (ICA) of the axisymmetric solar magnetic field. While PCA is effective in identifying the coherent modes that describe the 22 yr solar cycle, ICA uncovers the independent global modes the with characteristic 1 to 2.5 yr quasi periods observed in heliospheric and helioseismic time series. Five modes capture the salient properties of the data. Two modes describe the polar and high latitude fields, and present 1-1.5 yr quasi periodicities. The other three modes correspond to low and mid-latitude phenomena and show both 1.3 yr and 1.7 yr variations. Title: The Radial Dependence of Solar Energetic Particle Fluxes Authors: Ruzmaikin, Alexander; Li, Gang; Zank, Gary; Feynman, Joan; Jun, Insoo Bibcode: 2005ESASP.592..441R Altcode: 2005soho...16E..77R; 2005ESASP.592E..77R No abstract at ADS Title: Quasi periodicities in the Fluctuations of the Axisymmetric Solar Magnetic Field from Independent Component Analysis Authors: McDonald, D. P.; Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. Bibcode: 2005AGUSMSP43B..05M Altcode: Observed solar, interplanetary and geomagnetic time series contain quasi periodicities on the order of 1 to 2.5 years. The further discovery of 1.3 year fluctuations in helioseismic observations suggests that a variety of signals may be related to the underlying dynamo in the Sun. We have applied the methods of principal component analysis (PCA) and independent component analysis (ICA) to search for the coherent structures (PCA) and independent global modes (ICA) of the axisymmetric solar magnetic field. While PCA was shown to be effective in identifying the coherent modes that describe the 22 yr solar cycle, ICA uncovers the independent global modes with characteristic 1 to 2.5 yr quasi periods observed in heliospheric and helioseismic time series. We found that five modes effectively describe the data in both spatial and temporal domains. Two modes describe the polar and high latitude fields, and present 1-1.5 year quasi periodicities. The other three modes correspond to low and mid-latitude phenomena and show both 1.3 year and 1.7 year variations. By comparing the characteristic timescales, dates of occurrence and heliocentric latitudes of these modes, we connect them to their manifestations in heliospheric time series. Title: Coherent Structures and Rotation Rates in Coronal Activity, from Principal Component Analysis Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. Bibcode: 2005AGUSMSP21B..07C Altcode: Principal component analysis (PCA) offers a way to extract those structures that remain spatially coherent throughout a time series. We apply this method to a ~ 28 year time series of Wilcox Solar Observatory Carrington rotation maps (CR) of the 3.25 R coronal source surface field obtained via a potential field extrapolation. We find that over 99% of the variance is contained in the first eight modes. Mode 1, carrying 81.5% of the variance, and modes 2 and 3 containing 13% of the variance, have "dipole" structures. Modes 4-8, with a "quadruple" structure, contain 4.5% of the variance. The principal components (PCs) give the time dependence of the modes. We combine the PCs of modes 2 and 3 to get the amplitude and phase of a structure that behaves essentially as a dipole in the equatorial plane. During activity minima the structure is relatively weak and rotates at the 27.275 day Carrington rate. During the active periods of cycles 21 and 22 the amplitude is large and highly intermittent, and the dipole rotates more rapidly than the Carrington rate with a synodic period of 26.6 days. During cycle 23, however, the dipole moves backward in Carrington longitude with a synodic period of 27.8 days. The average of these is ~ 27.0 days, though this is actually realized only sporadically. The phase changes that occur at shorter time scales and that coincide with intermittent changes in the dipole amplitude seem to represent essentially random effects of the passage of the magnetic field through the convection zone. While the lower modes tend to lock the hemispheres together the higher modes present separate Northern and Southern hemisphere quadrupole-type patterns that drift in Carrington longitude similarly to the equatorial dipole. Over some periods the drift in each hemisphere closely tracks the other over a wide range of timescales. However, there are large, decadal-scale excursions in which first one hemisphere leads in phase by 3 or 4 rotations and then the other leads by a similar amount. Title: Independent Global Modes of Solar Magnetic Field Fluctuations Authors: Cadavid, A. C.; Lawrence, J. K.; McDonald, D. P.; Ruzmaikin, A. Bibcode: 2005SoPh..226..359C Altcode: Observed solar, interplanetary and geomagnetic time series contain quasi periodicities on scales of 1-2.5 years. The further discovery of 1.3 year fluctuations in helioseismic observations suggests that a variety of signals may be related to the underlying dynamo in the Sun. We use independent component analysis to study the temporal and spatial variations of a few statistically independent global modes of the axisymmetric solar magnetic field over a period of 25 years. Five modes capture the salient properties of the data. Two modes describe the polar and high latitude fields, and present 1-1.5 year quasi periodicities. The other three modes correspond to low and mid-latitude phenomena and show both 1.3 and 1.7-year variations. By comparing the characteristic time scales, dates of occurrence and heliocentric latitudes of these modes, we connect them to their manifestations in heliospheric time series. Title: Principal Component Analysis of the Solar Magnetic Field I: The Axisymmetric Field at the Photosphere Authors: Lawrence, John K.; Cristina Cadavid, Ana; Ruzmaikin, Alexander Bibcode: 2004SoPh..225....1L Altcode: A principal component analysis, or proper orthogonal decomposition, of the axisymmetric magnetic field at the photosphere is carried out to find an optimal representation of the observed solar cycle. The 22-year periodic field requires just two modes. NSO Kitt Peak synoptic maps for Carrington rotations 1664-2007 were reduced by taking both the mean and the median field over longitude to produce two sequences of functions of sine latitude spanning 25.7 years. The lowest modes of each are determined by the polar fields. The mean field is most efficient at representing the periodic field, but the median field is more efficient at representing the evolution of the diffuse field patterns. Title: The pattern of northern hemisphere surface air temperature during prolonged periods of low solar output Authors: Ruzmaikin, Alexander; Feynman, Joan; Jiang, Xun; Noone, David C.; Waple, Anne M.; Yung, Yuk L. Bibcode: 2004GeoRL..3112201R Altcode: We show that the reconstructed sensitivity of the sea level temperature to long term solar forcing in the Northern Hemisphere is in very good agreement with the empirical temperature pattern corresponding to changes of the North Annular Mode (NAM). This implies that long-term variations of solar output affect climate predominantly through the NAM that extends throughout the stratosphere and troposphere. Title: The Influence of the QBO and Solar Variability on the North Annular Mode. Authors: Ruzmaikin, A.; Feynman, J.; Jiang, X.; Camp, C. D.; Yung, Y. Bibcode: 2004AGUSM.A14A..05R Altcode: The Quasi-Biennial Oscillations (QBO) and solar variability are two natural stratospheric forcings affecting atmospheric dynamics and possibly climate. We study how these forcings affect the major mode of the wintertime atmospheric variability in the Northern Hemisphere, the North Annular Mode (NAM). This mode extends from the top of the stratosphere through the troposphere to sea level accounting for 22% of the variance in geopotential heights at sea level and more in the stratosphere (Thompson and Wallace, 1998; Baldwin and Dunkerton, 1999). It has been found (Ruzmaikin and Feynman, 2002) that the NAM of the coupled troposphere-stratosphere is influenced by decadal solar variability. But the influence depends on the phase of the QBO and phase of the winter season. Thus, in early (late) winter for the West (East) QBO, the NAM is more positive for low UV than for high UV fluxes. The effect was shown to be statistically significant. Here we present the results of our search for a physical mechanism by which the QBO and solar variability combined with seasonality affect the NAM. Because the NAM is excited in the interplay between the planetary waves and mean zonal wind (see for example Limpasuvan and Hartmann, 2000), we investigate the latitudinal, vertical and time distributions of the wave (EP) fluxes employing the NCEP Reanalysis Data and the ECMWF Data. We also investigate the possible effect of the QBO associated circulation on the NAM. References: Baldwin, M. P. and T. J. Dunkerton, J. Geophys. Res. 104, 30,937, 1999; Limpasuvan, V., and D. L. Hartmann, J. of Climate, 4414, 2000; Ruzmaikin, A., J, Feynman, J. Geophys. Res., 107, D14, 10.1029/2001JD001239, 2002; Thompson, D. W. J. and J. M. Wallace, Geophys. Res. Lett., 25, 1297, 1998. Title: Principal Component Analysis of the Latitudinal and Longitudinal Structure of the Photospheric Magnetic Cycle Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. Bibcode: 2004AAS...204.3708L Altcode: 2004BAAS...36Q.710L We average magnetic fields in NSO synoptic maps over longitude and bin the result by sin(latitude). Also, we average over a band of latitudes and bin by longitude. A time stack of one-dimensional latitude "images" resembles the Maunder butterfly diagram. Time stacks of longitude "images" can be re-mapped to arbitrary rotation periods.

Principal component analysis recombines images in a stack into mutually orthogonal "empirical orthogonal functions" (EOFs). The EOFs are ordered by how well each correlates with the full set of images. The principal components (PCs) give the evolution of each EOF as a function of any ordering parameter, such as time. The original data can be wholly or partially reconstructed from subsets of the EOFs and their PCs.

Our latitudinal EOFs have a few leaders whose PCs show both the 11/22-year cycle and repeating substructure. Following are EOFs whose PCs show the cycle but no repeated substructure. Next are EOFs with small scale structure independent of the cycle. The least correlated EOFs contain high latitude, mostly unipolar fields. We suggest associating these four subsets of the EOFs with, respectively, global dynamo toroidal fields, turbulently disordered structures fed by the toroidal fields, a possible local surface dynamo process, and a global poloidal component.

We also studied a stack of longitudinal images of fields that were averaged over latitude between N25 and N35 degrees. Two especially active longitudes 180 degrees apart rotate with a period of 27.8 days. Structure at these longitudes dominates the leading EOFs. The corresponding PCs are active over the whole span of the data.

This work was supported by NASA Grant NAG5-10880. NSO/Kitt Peak data used here are produced cooperatively by NSF/NOAO, NASA/GSFC, and NOAA/SEL. Title: Two-dimensional Empirical Orthogonal Functions of the Photospheric Magnetic Cycle Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. Bibcode: 2004AAS...204.3707C Altcode: 2004BAAS...36Q.710C We carried out a principal component analysis (PCA) on sequences of NSO magnetic flux synoptic maps by Carrington rotation. Two data sets were investigated: (i) a sequence of 364 images from Carrington rotation 1625 to 2007, with image size 360 x 180 pixels (1 degree/pixel in longitude and sin(latitude)*90 in latitude for both hemispheres); (ii) a sequence of 79 higher resolution maps of size 1800 x 900 pixels starting at Carrington rotation 1913. The PCA of a time series yields an eigenvalue spectrum, the corresponding eigenfunctions (modes or "empirical orthogonal functions" (EOFs)), and the principal components which describe the time evolution of the modes. The dominant EOFs are associated with those structures that remain spatially coherent throughout intervals of the time series, and correspond to the functions with the highest eigenvalues. If the eigenvalue spectrum is dominated by only a few large members, then the corresponding few EOFs will mainly characterize the data. The rest will contain transient fluctuations. We apply the technique to the two dimensional maps and determine which EOFs dominate during different times of the solar cycle. We find that the dominant modes are associated with the active part of the cycle as expected, while the weaker modes characterize the quiet periods. The increasing and declining phases are associated with modes of intermediate eigenvalues. We reconstruct the time series by projecting onto the three classes of modes and investigate the probability distribution function (PDF) of "projected" magnetic flux. We compare these results to the PDFs obtained from artificial data generated by dynamo models. This work was supported in part by Grant NASA-NAG5-10880. NSO/Kitt Peak data used here are produced cooperatively by NSF/NOAO, NASA/GSFC, and NOAA/SEL. Title: The Sun's Preferred Longitudes and the Coupling of Magnetic Dynamo Modes Authors: Bigazzi, Alberto; Ruzmaikin, Alexander Bibcode: 2004ApJ...604..944B Altcode: 2003astro.ph.12212B Observations show that solar activity is distributed nonaxisymmetrically, concentrating at ``preferred longitudes.'' This indicates the important role of nonaxisymmetric magnetic fields in the origin of solar activity. We investigate the generation of the nonaxisymmetric fields and their coupling with the axisymmetric solar magnetic field. Our kinematic generation (dynamo) model operating in a sphere includes a model of solar differential rotation, as obtained by inversion of helioseismic data, modeled distributions of the turbulent resistivity, nonaxisymmetric mean helicity, and meridional circulation in the convection zone. We find that (1) the nonaxisymmetric modes are localized near the base of the convection zone, where the formation of active regions starts, and at latitudes around 30° (2) the coupling of nonaxisymmetric and axisymmetric modes causes the nonaxisymmetric mode to follow the solar cycle; the phase relations between the modes are found; and (3) the rate of rotation of the first nonaxisymmetric mode is close to that determined in interplanetary space. Title: A High-Speed Erupting-Prominence CME: A Bridge Between Types Authors: Feynman, Joan; Ruzmaikin, Alexander Bibcode: 2004SoPh..219..301F Altcode: Several studies have indicated that there may be two distinct types of coronal mass ejections (CMEs); a high-velocity bright energetic type associated with flares, and a smaller slower less impressive type associated with erupting prominences. How valid is this distinction? We analyze a CME combining attributes of both types, a high-velocity bright CME associated with an erupting prominence. A study of this event and several others allows us to argue that the apparent differences separating the two types may be an observational effect. Our results are consistent with a single CME process for both flare-associated and filament-associated CMEs. This process consists of three stages. The initial stage is brought about by the emergence of new magnetic flux, which interacts with the pre-existing magnetic configuration and results in a slow rise of the magnetic structure, which later becomes the CME. The second stage is a fast reconnection phase with flaring and a sudden increase of the rise velocity of the magnetic structure. It also includes a rapidly increasing CME acceleration followed by a rapidly falling acceleration. The third stage or CME propagation stage shows only slow changes in the acceleration and finally the velocity becomes constant. LASCO observes only the third stage. The differences found between observed flare-associated and prominence-associated CME velocity behavior appear to be primarily due to the relative heights in the corona at which the erupting structures form. Title: A simple model of solar variability influence on climate Authors: Ruzmaikin, Alexander; Lawrence, John K.; Cadavid, Ana Cristina Bibcode: 2004AdSpR..34..349R Altcode: We present a simple dynamic model of solar variability influence on climate, which is truncated from the stratospheric wave-zonal flow interaction dynamics over a β-plane. The model consists of three ordinary differential equations controlled by two parameters: the initial amplitude of planetary waves and the vertical gradient of the zonal wind. The changes associated with the solar UV variability, as well as with seasonal variations, are introduced as periodic modulations of the zonal wind gradient. Influence of the Quasi-Biennial Oscillation is included as a periodic change of the width of the latitudinal extent of the β-plane. The major climate response to these changes is seen through modulation of the number of cold and warm winters. Title: Preferred longitudes and the solar dynamo. Authors: Bigazzi, A.; Ruzmaikin, A. Bibcode: 2004cosp...35.3578B Altcode: 2004cosp.meet.3578B Magnetic activity in the Sun tends to cluster at preferred longitudes, giving rise to non-axisymmetric structures. The origin of this phenomenon is unclear. Dynamo theory has not consistently addressed this outstanding feature of solar magnetism, so far. We discuss the dynamics of the non--axisymmetric modes of the large--scale fields and show its possible connections with the phenomena of preferred longitudes and the clustering of magnetic activity. In our mean--field model, a non-axisymmetric alpha-effect, possibly originating from instabilities of the flow field, couples together the longitudinal modes of the dynamo. The amplitude of the modes thus generated is modulated in time following the solar cycle, in agreement with the observed phase shift between the axisymmetric field, which reaches its largest amplitude close to solar minimum, and the non-axisymmetric field, which is larger close to solar maximum. Unlike the axisymmetric fields, the non-axisymmetric ones are influenced by the radial structure of the solar rotation rate. As a result, they concentrate in a region around 30° latitude, where the radial gradient of the solar rotation is minimal as shown by helioseismology. This may contribute to understanding the origin of the latitudinal distribution of sunspots through the cycle. The non-axisymmetric modes represent rigid patterns rotating in longitude with a rate determined by the solutions of the dynamo equations. This rate can be measured and checked against that of the oscillating magnetic features found in the interplanetary medium, or against the rotation rate of the tilted dipole field reconstructed during the last fast scan of the Ulysses spacecraft, returning a value close to the core rotation rate. Title: Influence of Photospheric Magnetic Fields and Dynamics on Chromospheric K-Line Emission Authors: Lawrence, J. K.; Cadavid, A. C.; Miccolis, D.; Berger, T. E.; Ruzmaikin, A. Bibcode: 2003ApJ...597.1178L Altcode: We analyze a 9 hr sequence of simultaneous, high-resolution, high-cadence G-band and K-line solar filtergrams plus magnetograms of lower cadence and resolution. Images include both network and internetwork. The magnetic and filtergram intensities, their fluctuations, and relative phases change with progressive strengthening of local magnetic field. At increased flux levels, sudden photospheric downflows create long-lived magnetic elements. For weak magnetic fields the K-line and G-band intensities include an oscillatory component with period 4 minutes. For stronger fields, the K-line period shifts to 5 minutes, while the G-band fluctuations fade due to dissociation of their source, the CH radical. These K-line and G-band fluctuations, whose periods are longer than the acoustic cutoff, are coherent and in phase. They also are coherent with fluctuations of the magnetic field. Weak-field magnetic fluctuations lead the intensity fluctuations by a phase shift of 90°. Strong-field magnetic fluctuations trail the intensities by 100°. These are interpreted as standing waves in the photosphere and low chromosphere. Another class of G-band fluctuations, with periods shorter than the acoustic cutoff, is associated both with stronger magnetic fields and with enhanced K-line emission with fluctuations longer than the cutoff period. This suggests waves excited by rapid photospheric perturbations and propagating up along magnetic flux tubes. Title: Multi-Angle Viewing of the Sun and the Inner Heliosphere Authors: Ruzmaikin, Alexander Bibcode: 2003AIPC..679..826R Altcode: We describe the concept of a proposed mission, called Multi-Angle Solar Sources Explorer (MASSÉ), that would observe the Sun and the inner Heliosphere from an orbit at 0.72 AU over all solar longitudes. It would, in coordination with observations from Earth's side, investigate the sources of solar activity from their origin deep within the Sun, their emergence onto the photosphere, and their ejection into the Heliosphere. It carries a Doppler-magnetic imager, and in situ energetic particle, solar wind, and magnetic field detectors. Three-dimensional views of the convection zone, where solar activity originates, are reconstructed by correlating MASSÉ and earth-side Doppler signals from acoustic wave packets traversing deep solar layers. Magnetic images reveal the evolution of active regions over their life-time and allow the study of emerging fields from deep layers. Particle, plasma, and magnetic field data provide information on the sites and mechanisms of acceleration of hazardous high-energy particles produced by coronal mass ejections. Title: Influence of Photospheric Magnetism and Dynamics on Chromospheric K-line Emission Authors: Lawrence, J. K.; Cadavid, A. C.; Miccolis, D.; Berger, T. E.; Ruzmaikin, A. Bibcode: 2003SPD....34.0704L Altcode: 2003BAAS...35..820L We analyze a unique 9 hr sequence of near simultaneous, high resolution and high cadence G-band and K-line SVST solar filtergrams together with magnetograms of lower cadence and resolution. We focus on a region of the solar surface that includes both internetwork and network. We examine how the (temperature minimum/chromospheric) CaII K-line and (photospheric) G-band intensities, their temporal fluctuations and their coherence and phase relations, with each other and with magnetic fluctuations, change as we progress from weak magnetic fields (internetwork) to intermediate and strong fields (network).

As the background level of flux is increased, sudden photospheric downflow events can create long-lived, compact (i.e. network) magnetic elements. For weak magnetic fields the K-line and G-band intensity signals show an oscillatory component with period centered on 4 min. As we pass to strong fields, the K-line signal shifts to a 5 min period while the G-band signal fades, presumably due to dissociation of the CH radical. The K-line and G-band signals are coherent and nearly in-phase. They are both coherent with fluctuations of the magnetic field. For weak field the magnetic signal leads the intensity signals by 90o in phase. For intermediate and strong fields the magnetic signal trails the intensities by 110o. We interpret this as a transition from acoustic standing waves with weak, passive magnetic field to a slow mode trapped magnetoacoustic wave. For intermediate magnetic field we find, in addition to the coherent waves, that G-band fluctuations at frequencies above the acoustic cutoff (period < 3.5 min) are associated with magnetic fields and with K-line emission at periods > 3.5 min. This suggests the presence of flux tube waves excited by rapid photospheric perturbations.

This work was supported by grants NSF-ATM 9987305 and NASA-NAG5-10880. The SVST is operated by the Swedish Royal Academy of Sciences at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. Title: A Simple Model of Stratospheric Dynamics Including Solar Variability. Authors: Ruzmaikin, Alexander; Lawrence, John; Cadavid, Cristina Bibcode: 2003JCli...16.1593R Altcode: A simple dynamic model, truncated from the stratospheric wave-zonal flow interaction Holton and Mass model, is introduced and studied. This model consists of three ordinary differential equations controlled by two parameters: the initial amplitude of planetary waves and the vertical gradient of the zonal wind. The changes associated with seasonal variations and with the solar variability are introduced as periodic modulations of the zonal wind gradient. The major climatic response to these changes is seen through modulation of the number of cold and warm winters. Title: Photospheric Sources of Chromospheric Dynamics in the Internetwork Authors: Cadavid, A. C.; Lawrence, J. K.; Berger, T. E.; Ruzmaikin, A. Bibcode: 2003SPD....34.0703C Altcode: 2003BAAS...35..820C We analyze a unique 9 hr sequence of near simultaneous, high resolution and high cadence G-band and K-line solar filtergrams together with magnetograms of lower cadence and resolution, taken with the SVST. We investigate an internetwork region characterized by magnetic fields with strength < 150 Gauss and focus on the phenomena surrounding discrete photospheric darkening ``events'' in G-band intensities. 72 % of the darkenings are followed after 2 min by K-line brightenings. In the remaining cases the darkenings are instead preceded by K-line brightenings 2 min earlier. In both cases the preceding and following G-band minima are each associated with transient magnetic enhancements, and thus, presumably, photospheric inflows followed by outflows. The magnetic field appears to have no role in coupling the photospheric phenomena to the chromosphere, and acts as a passive tracer of horizontal photospheric flows that converge on the photospheric darkening events and then rebound. The timing and coupling of the photospheric darkenings and chromospheric brightenings appear to be regulated by a pre-existing 4 min oscillation of the solar atmosphere. Other oscillations with periods in the range 1-8 min also are present, and in general the wave power is doubled at the time of an event. At short periods temporal structure is resolved. Our results favor an acoustic source for enhanced amplitudes of K-line intensity oscillations. Title: Photospheric Sources and Brightening of the Internetwork Chromosphere Authors: Cadavid, A. C.; Lawrence, J. K.; Berger, T. E.; Ruzmaikin, A. Bibcode: 2003ApJ...586.1409C Altcode: We analyze a unique 9 hr sequence of near-simultaneous, high-resolution and high-cadence G-band and K-line solar filtergrams, together with magnetograms of lower cadence and resolution. Our focus is on the phenomena surrounding discrete photospheric darkening ``events'' in internetwork G-band intensities. 72% of the darkenings are followed after 2 minutes by K-line brightenings. In the remaining cases, the darkenings are instead preceded by K-line brightenings 2 minutes earlier. Equivalent results are found when reference is shifted to K-line brightening events, although these two sets overlap by no more than 15%. The timing and coupling of the photospheric darkenings and chromospheric brightenings appear to be regulated by a preexisting 4 minute oscillation of the solar atmosphere. Other oscillations with periods in the range 1-8 minutes also are present, and in general the wave power is doubled at the time of an event. Our results favor an acoustic source for enhanced amplitudes of K-line intensity oscillations. The magnetic field acts as a passive tracer of horizontal photospheric flows that converge on the photospheric darkening events and then rebound. Title: Signs of magnetic helicity in interplanetary coronal mass ejections and associated prominences: Case study Authors: Ruzmaikin, Alexander; Martin, Sara; Hu, Qiang Bibcode: 2003JGRA..108.1096R Altcode: We study the distribution of magnetic helicity in interplanetary coronal mass ejections (CMEs) separated into magnetic clouds and remnants of the prominence structures for three cases with identified remnants of prominences. The magnetic configurations of magnetic clouds and prominence remnants can satisfactorily be described by the flux rope approximation. It is shown that the magnetic helicities in both parts of the CMEs have the same sign. This sign is consistent with the dominance of CMEs with negative helicity in the northern hemisphere and positive in the southern hemisphere. The results are discussed in the context of different models of CME eruption at the Sun. Title: Helioseismic probing of the solar dynamo Authors: Ruzmaikin, Alexander; Lindsey, Charles Bibcode: 2003ESASP.517...71R Altcode: 2003soho...12...71R According to theoretical predictions, the solar dynamo operating in the convection zone generates maximal magnetic fields near the base of the convection zone. Detection of this field is a challenging task for helioseismology. We discuss the ways of probing the magnetic field in the solar interior and estimate the magnitude of the field that can be detected with presently achievable accuracy. It is easier, however, to detect the flows that drive the dynamo. We describe the major flow parameters related to the dynamo flows and present the requirements for measurement of these parameters with local helioseismic techniques. Title: The magnetic field in the convection zone Authors: Bigazzi, Alberto; Ruzmaikin, Alexander A. Bibcode: 2003ESASP.517..239B Altcode: 2002astro.ph.11116B; 2003soho...12..239B One of the key questions in solar physics that remains to be answered concerns the strength and the distribution of the magnetic fields at the base of the convection zone. The flux tube dynamics requires that toroidal fields of strength as large as 100 kilogauss be present at the base of the convection zone. The kinetic-magnetic equipartition argument leads to smaller field strengths. For possible detection of these relatively small (compared to pressure effects) fields by helioseismic methods it is important to know the range of the field strengths and their distribution. We estimate a range for the toroidal magnetic field strengths at the base of the convection zone using dynamo simulations in a spherical shell. These simulations involve the distribution of rotation provided by helioseismic inversions of the GONG and MDI data. Combining the simulations with the observed line-of-sight surface poloidal field we extract the spatial pattern and magnitude of the mean toroidal magnetic field at the base of the convection zone. Title: The JPL proton fluence model: an update Authors: Feynman, Joan; Ruzmaikin, Alexander; Berdichevsky, Victor Bibcode: 2002JASTP..64.1679F Altcode: 2002JATP...64.1679F The development of new technologies and the miniaturization of sensors bring new requirements for our ability to predict and forecast hazardous space weather conditions. Of particular importance are protons in the energy range from 10s to 100s of MeV which cause electronic part and solar cell degradation, and pose a hazard to biological systems in space and to personnel in polar orbit. Sporadic high-energy solar particle events are a main contributor to the fluences and fluxes of such protons. A statistical model, JPL 1991 (J. Geophys. Res. 98 (1991) 13,281), was developed to specify fluences for spacecraft design and is now widely used. Several major solar proton events have occurred since that model was developed and one objective of this paper is to see if changes need to be made in the model due to these recent events. Another objective is to review the methods used in JPL 1991 in the light of new understandings and to compare the JPL methods with those used in other models. We conclude that the method used in developing JPL 1991 model is valid and that the solar events occurring since then are completely consistent with the 1991 model. Since no changes are needed we suggest that the name of the model be changed to ``the JPL fluence model''. Title: Multi-angle exploration of the Sun Authors: Ruzmaikin, Alexander Bibcode: 2002ESASP.505...53R Altcode: 2002IAUCo.188...53R; 2002solm.conf...53R We describe the concept of a proposed new mission, called Multi-Angle Solar Sources Explorer (MASSÉ), that would observe the Sun from an orbit at 0.72 AU and over all solar longitudes. It would, in coordination with observations taken from Earth's side, investigate the sources of solar activity from their origin deep within the Sun, their emergence onto the photosphere, and their ejection into the heliosphere. It carries a Doppler-magnetic imager, and in situ energetic particle, solar wind, and magnetic field detectors. Three-dimensional views of the convection zone, where solar activity originates, are reconstructed by correlating MASSÉ and Earth-side Doppler signals from acoustic wave packets traversing deep solar layers. Magnetic images reveal the evolution of active regions over the entire solar surface and allow the study of emerging fields from deep layers. MASSÉ particle, plasma, and magnetic field data provide information on the sites and mechanisms of acceleration of hazardous high-energy particles produced by coronal mass ejections. Title: Observations of the Structure of small scale photospheric fields Authors: Lawrence, J.; Cadavid, A.; Ruzmaikin, A.; Berger, T. Bibcode: 2002ocnd.confE..26L Altcode: No abstract at ADS Title: A simple model of solar variability influence on climate. Authors: Ruzmaikin, A.; Lawrence, J.; Cadavid, A. Bibcode: 2002cosp...34E.336R Altcode: 2002cosp.meetE.336R We introduce and study a simple dynamic model of solar influence on climate. The model is truncated from the stratospheric wave-zonal flow interaction model suggested by Holton and Mass (1976). Our model consists of three ordinary differential equations controlled by two parameters: the initial amplitude of planetary waves and the vertical gradient of the zonal wind. The changes associated with seasonal variations and with the solar variability are introduced as periodic modulations of the zonal wind gradient. The major atmospheric response to these changes is seen through modulation of the number of cold and warm winters. Title: A search for the source spectrum of solar wind fluctuations Authors: Ruzmaikin, Alexander Bibcode: 2001ESASP.493..455R Altcode: 2001sefs.work..455R No abstract at ADS Title: Strength and phase of the solar dynamo during the last 12 cycles Authors: Ruzmaikin, A.; Feynman, J. Bibcode: 2001JGR...10615783R Altcode: We use the aa index of geomagnetic activity recorded for 130 years to study the strength and phase properties of the solar dynamo. We split the monthly averaged aa into two parts: one part proportional to the sunspot number and the other part proportional to the residual. We argue that the first part is a proxy for the solar dynamo's large-scale mean toroidal magnetic field. The residual has the same periodicity as the sunspot cycle and has closely related amplitude, but is shifted in phase. We relate this residual to the poloidal field generated from the toroidal field in the dynamo process. The changes in both components demonstrate that there was a long-term trend in the strength and relative phases of the toroidal and poloidal components of the mean-field dynamo. The changes in the relative phase of the toroidal and poloidal fields suggest that the distributions of the differential rotation and helicity within the Sun's convection zone have changed over timescales of 50 years. Title: Mesogranulation and Turbulence in Photospheric Flows Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. Bibcode: 2001SoPh..202...27L Altcode: 2001astro.ph..4354L Below the scale of supergranules we find that cellular flows are present in the solar photosphere at two distinct size scales, approximately 2 Mm and 4 Mm, with distinct characteristic times. Simultaneously present in the flow is a non-cellular component, with turbulent scaling properties and containing 30% of the flow energy. These results are obtained by means of wavelet spectral analysis and modeling of vertical photospheric motions in a 2-hour sequence of 120 SOHO/MDI, high-resolution, Doppler images near disk center. The wavelets permit detection of specific local flow patterns corresponding to convection cells. Title: Spatiotemporal Scaling of Solar Surface Flows Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A.; Berger, T. E. Bibcode: 2001PhRvL..86.5894L Altcode: 2001astro.ph..1224L The sun provides an excellent natural laboratory for nonlinear phenomena. We use motions of magnetic bright points on the solar surface, at the smallest scales yet observed, to study the small scale dynamics of the photospheric plasma. The paths of the bright points are analyzed within a continuous time random walk framework. Their spatial and temporal scaling suggests that the observed motions are the walks of imperfectly correlated tracers on a turbulent fluid flow in the lanes between granular convection cells. Title: Preferred solar longitudes with signatures in the solar wind Authors: Ruzmaikin, A.; Feynman, J.; Neugebauer, M.; Smith, E. J. Bibcode: 2001JGR...106.8363R Altcode: Using spacecraft data collected over three solar cycles, Neugebauer et al. [2000] found a persistent dependence of the solar wind speed and the radial component of the interplanetary magnetic field on solar longitude, defined in a coordinate system with a rotation period of 27.03 days. Here we investigate the solar source of this period using observations of the photospheric magnetic field. We study the lowest-order nonaxisymmetric modes of the solar field extracted from synoptic charts of the Wilcox Solar Observatory. We find there is a robust magnetic structure on the Sun, which rotates with the period found by Neugebauer et al. [2000] in the solar wind. This rotation is more rapid than the solar equatorial and core rotations. We discuss the association of this nonaxisymmetric mode with the magnetic field generated by the solar mean field dynamo. Title: Magnetic Footpoint Motions and Superdiffusion Authors: Cadavid, C.; Lawrence, J.; Ruzmaikin, A. Bibcode: 2001AGUSM..SP51B07C Altcode: In order to study the properties of the velocities of magnetic foot points in the photosphere, we analyzed the dynamics of magnetic G-band bright points (MBP's) from data obtained at the Swedish Vacuum Solar Telescope. Almost universally, random walks and diffusion are studied by looking at the square of the displacement of an average fluid element in a given time. For normal diffusion the scaling exponent that describes the relation of the mean squared displacement to the time has a value of 1. However this approach is inadequate for the study of the observed motions, since the magnetic features are stopped in their motion at ``traps'' in the intergranular lanes. Additionally we only have access to a limited amount of data. A more reliable characterization of the fluid motions is obtained from low statistical moments, such as the square root, or lower, of the displacements. In this case the scaling exponent is 1.4. The motions are therefore superdiffusive: faster than normal but slower than purely fluid turbulence. This not only reveals turbulent dynamics between convection cells on the Sun, but also gives quantitative information on the coupling of magnetic fields to the solar flows. In turn these superdiffusive motions can be used to drive the footpoints of magnetic flux tubes in a model of chromospheric heating. This is a more realistic approach than using Gaussian noise to approximate the turbulence component to the velocity field. Title: Mesogranulation and Turbulence in Photospheric Flows Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. Bibcode: 2001AGUSM..SP41C02L Altcode: Cellular flows are present in the solar photosphere at two distinct size scales, 2 Mm and 4 Mm, with distinct characteristic times. Simultaneously present in the flow is a non-cellular component, with turbulent scaling properties between 1 Mm and 64 Mm, and containing 30 % of the flow energy. These results are obtained by means of wavelet spectral analysis and modeling of vertical photospheric motions in a 2-hour sequence of 120 SOHO/MDI, high resolution, Doppler images near disk center. The wavelets permit detection of specific local flow patterns corresponding to convection cells. Standard spectral techniques have difficulty resolving mesogranules for three basic reasons: (1) the mesogranules are near in scale to granules and weaker in velocity and (2) they are hidden by overlying turbulence because (3) global basis functions, such as Fourier waves or spherical harmonics, do not allow attention to be paid to the local topologies that label cellular flows. Title: Origin of Sunspots Authors: Ruzmaikin, Alexander Bibcode: 2001SSRv...95...43R Altcode: Sunspots, seen as cool regions on the surface of the Sun, are a thermal phenomenon. Sunspots are always associated with bipolar magnetic loops that break through the solar surface. Thus to explain the origin of sunspots we have to understand how the magnetic field originates inside the Sun and emerges at its surface. The field predicted by mean-field dynamo theories is too weak by itself to emerge at the surface of the Sun. However, because of the turbulent character of solar convection the fields generated by dynamo are intermittent - i.e., concentrated into ropes or sheets with large spaces in between. The intermittent fields are sufficiently strong to be able to emerge at the solar surface, in spite of the fact that their mean (average) value is weak. It is suggested here that magnetic fields emerge at the solar surface at those random times and places when the total magnetic field (mean field plus fluctuations) exceeds the threshold for buoyancy. The clustering of coherently emerged loops results in the formation of a sunspot. A non-axisymmetric enhancement of the underlying magnetic field causes in the clustering of sunspots forming sunspot groups, clusters of activity and active longitudes. The mean field, which is not directly observable, is also important, being responsible for the ensemble regularities of sunspots, such as Hale's law of sunspot polarities and the 11-year periodicity. Title: Rate of helicity production by solar rotation Authors: Berger, Mitchell A.; Ruzmaikin, Alexander Bibcode: 2000JGR...10510481B Altcode: In recent years, solar observers have discovered a striking pattern in the distribution of coronal magnetic structures: northern hemisphere structures tend to have negative magnetic helicity, while structures in the south tend to have positive magnetic helicity. This hemispheric dependence extends from photospheric observations to in situ measurements of magnetic clouds in the solar wind. Understanding the source of the hemispheric sign dependence, as well as its implications for solar and space physics has become known as the solar chirality problem. Rotation of open fields creates the Parker spiral which carries outward 1047Mx2 of magnetic helicity (in each hemisphere) during a solar cycle. In addition, rough estimates suggest that each hemisphere sheds on the order 1045Mx2 in coronal mass ejections each cycle. Both the α effect (arising from helical turbulence) and the Ω effect (arising from differential rotation) should contribute to the hemispheric chirality. We show that the Ω effect contribution can be captured in a surface integral, even though the helicity itself is stored deep in the convection zone. We then evaluate this surface integral using solar magnetogram data and differential rotation curves. Throughout the 22 year cycle studied (1976-1998) the helicity production in the interior by differential rotation had the correct sign compared to observations of coronal structures-negative in the north and positive in the south. The net helicity flow into each hemisphere over this cycle was approximately 4×1046Mx2. For comparison, we estimate the α effect contribution; this may well be as high or higher than the differential rotation contribution. The subsurface helicity can be transported to the corona with buoyant rising flux tubes. Evidently only a small fraction of the subsurface helicity escapes to the surface to supply coronal mass ejections. Title: Response to weak solar forcing in a general circulation model of the atmosphere. Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A. Bibcode: 2000BAAS...32R.832C Altcode: No abstract at ADS Title: Random Walks of Magnetic Bright Points and Coronal Loop Heating Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 2000AAS...196.4903L Altcode: 2000BAAS...32..750L The random walks of small-scale ( ~ 0.2 arcsec) magnetic bright points (MBPs) in the lanes between photospheric granules are anomalous. The temporal growth of the q-th moment of the displacement r(t) is a power law with exponent q γ (q)/2. For normal, Gaussian walks γ (q)= 1 for all q. However, for the MBP walks on time scales < 45 minutes we find that γ (2)<1 and that γ (q) is a decreasing function of q. Many viable models for the heating of coronal loops are based on the additon of energy via twisting and braiding of magnetic flux lines by the random motions of their footpoints. If the MBPs are associated with such footpoints, then the statistics of their motions are directly relevant to coronal heating. For example, a number of models derive heating rates based on moments of the displacements and include the standard assumption that γ = 1. However, this assumption is wrong for MBPs, and the actual value of γ depends on exactly which moment enters the expression. All such models are therefore subject to modification. The result γ (2)<1 is a result of pauses in the MBP walks on all time scales (''fractal time'') up to ~ 45 min. This implies that the motions of an individual footpoint are not statistically stationary. This in turn means that the injection of energy into a given loop will be strongly variable and intermittent. This can be related to observations of the details of variability in coronal loop emissions, giving information on the locations of energy deposition and on time scales of energy release. We thus hope to further constrain acceptable heating models. This work was supported in part by NSF Grant ATM-9628882. Title: Response to Weak Solar Forcing in a General Circulation Model of the Atmosphere Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A. Bibcode: 2000SPD....3102117C Altcode: 2000BAAS...32..832C We study the effect of variable external forcing on a dynamical system proposed by Lorenz as a simple general circulation model of the atmosphere. When a strong annual cycle is included, numerical exploration reveals the existence of a variety of multi-year climate states, which fall into two basic types. In the space of external forcing parameters, the different kinds of climate state are interleaved in an intricate pattern at scales < 0.01. This is below the ~ 0.1 level of observed solar cycle irradiance variability which can thus modulate the model climate state. If the solar cycle is accompanied by a steady drift in forcing, it can produce periodic modulation which appears, disappears and even reverses its phase. A parametric drift by itself produces intervals of steady, but sometimes differing, climates punctuated by intermittent bursts of variability. Different forcing parameters for the Northern and Southern Hemispheres produce different responses to variable forcing. Title: On the Nature and Persistence of Preferred Longitudes of Solar Activity. Authors: Ruzmaikin, A. A.; Feynman, J.; Neugebauer, M.; Smith, E. J. Bibcode: 2000SPD....31.0404R Altcode: 2000BAAS...32..835R Several studies of the distribution of activity on the solar surface indicate preferred longitude patterns sometimes lasting longer than a solar cycle. We have analyzed 150 years of daily sunspot number and find evidence for a preferred longitude zone that persisted over 13 solar cycles. The relative intensity of the preferred zone varied from cycle to cycle and, in some individual cycles the preference was not evident. This complements the recent analysis of the measured solar wind speed and interplanetary magnetic field over more than three solar cycles, which implied that the solar magnetic moment returned to the same longitude after each reversal (Neugebauer et al., JGR, 105, 2315, 2000). These findings suggest a long-term memory built into the mechanism generating the solar magnetic field responsible for the activity. The solar magnetic field is generated by a dynamo located near the bottom of the convection zone. A particular role is played by a thin tachocline layer on the border between the convection zone and the radiative core. The structure and motions inferred from helioseismic data and models do not, however, indicate any preferred longitude. Preferred longitudes can arise due to excitation of non-axisymmetric magnetic modes. These modes have been invoked for explanation of clustering of emerging activity (Ruzmaikin, Solar Phys., 182, 1, 1998). The solar magnetic moment is determined by the sum of the axisymmetric (m = 0) and the first non-axisymmetric (m = 1) mode. We will discuss the conditions of excitation and persistence of non-axisymmetric modes on the Sun implied by the results of our data analyses. The work was performed in part for the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Title: Can We Get the Bottom B? Authors: Ruzmaikin, Alexander Bibcode: 2000SoPh..192...49R Altcode: Understanding the solar dynamics and the origin of active regions depends crucially on our knowledge of the magnetic fields deep within the convection zone. Can we determine magnetic fields there? Some clues are given by dynamo theories and modeling of those instabilities in the convection zone which result in the emergence of magnetic flux. Magnetic field generated by dynamo is predominantly azimuthal and believed to be unstable to the formation of flux tubes. Simulations indicate that the emergence of the magnetic flux tubes strongly depends on the field strength and its longitudinal distribution at the bottom of the convection zone. In a unifying approach advocated in this paper the solar magnetic field is split into a mean part generated by the mean-field dynamo and a fluctuating part approximated by an ensemble of flux tubes. Observationally, the identification of the longitudinal distribution of emerging photospheric magnetic fields can give us information about the magnetic field strength at the bottom of the convection zone. Distinguishing between the modes of emerging field requires simultaneous magnetic imaging of both sides of the Sun. Correlation of simultaneous Dopplergrams of the photosphere from earthside and from the farside of the Sun opens an opportunity to detect velocity structures at the base of the convection zone, associated with the dynamo and emerging active regions. This global imaging of the photosphere can also be used for detection of a magnetic field in the solar core. Title: The solar magnetic field and the solar wind: Existence of preferred longitudes Authors: Neugebauer, M.; Smith, E. J.; Ruzmaikin, A.; Feynman, J.; Vaughan, A. H. Bibcode: 2000JGR...105.2315N Altcode: Direct measurements of the solar wind speed and the radial component of the interplanetary magnetic field acquired over more than three solar cycles are used to search for signatures of a persistent dependence of solar wind properties on solar longitude. Two methods of analysis are used. One finds the rotation period that maximizes the amplitude of longitudinal variations of both interplanetary and near-Earth data mapped to the Sun. The other is based on power spectra of near-Earth and near-Venus data. The two methods give the same result. Preferred-longitude effects are found for a synodic solar rotation period of 27.03+/-0.02 days. Such high precision is attained by using several hundred thousand hourly averages of the solar wind speed and magnetic field. The 27.03-day periodicity is dominant only over long periods of time; other periodicities are often more prominent for shorter intervals such as a single solar cycle or less. The 27.03-day signal is stronger and more consistent in the magnetic field than in the solar wind speed and is stronger for intervals of high and declining solar activity than for intervals of low or rising activity. On average, solar magnetic field lines in the ecliptic plane point outward on one side of the Sun and inward on the other, reversing direction approximately every 11 years while maintaining the same phase. The data are consistent with a model in which the solar magnetic dipole returns to the same longitude after each reversal. Title: Anomalous Diffusion of Solar Magnetic Elements Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A. Bibcode: 1999ApJ...521..844C Altcode: The diffusion properties of photospheric bright points associated with magnetic elements (magnetic bright points) in the granulation network are analyzed. We find that the transport is subdiffusive for times less than 20 minutes but normal for times larger than 25 minutes. The subdiffusive transport is caused by the walkers being trapped at stagnation points in the intercellular pattern. We find that the distribution of waiting times at the trap sites obeys a truncated Lévy type (power-law) distribution. The fractal dimension of the pattern of sites available to the random walk is less than 2 for the subdiffusive range and tends to 2 in the normal diffusion range. We show how the continuous time random walk formalism can give an analytical explanation of the observations. We simulate this random walk by using a version of a phenomenological model of renewing cells introduced originally for supergranules by Simon, Title, & Weiss. We find that the traps that cause the subdiffusive transport arise when the renewed convection cell pattern is neither fixed nor totally uncorrelated from the old pattern, as required in Leighton's model, but in some intermediate state between these extremes. Title: Can El Nińo amplify the solar forcing of climate? Authors: Ruzmaikin, A. Bibcode: 1999GeoRL..26.2255R Altcode: ENSO (El Nińo and the Southern Oscillation) is considered as a stochastic driver that excites the atmospheric anomaly states, such as Pacific North American pattern. This can make 11-year solar activity forcing of climate feasible through stochastic resonance-a mechanism that amplifies a weak input to a nonlinear bistable system by the assistance of noise. Title: Modulation of cosmic ray precipitation related to climate Authors: Feynman, J.; Ruzmaikin, A. Bibcode: 1999GeoRL..26.2057F Altcode: High energy cosmic rays may influence the formation of clouds and thus impact weather and climate. Due to systematic solar wind changes, the intensity of cosmic rays incident on the magnetopause has decreased markedly during this century. The pattern of cosmic ray precipitation through the magnetosphere to the upper troposphere has also changed. Early in the century, the part of the troposphere open to cosmic rays of all energies was typically confined to a relatively small high-latitude region. As the century progressed the size of this region increased by over 25% and there was a 6.5° equatorward shift in the yearly averaged latitudinal position of the subauroral region in which cloud cover has been shown to be cosmic ray flux dependent. We suggest these changes in cosmic ray intensity and latitude distribution may have influenced climate change during the last 100 years. Title: Three-dimensional Magnetohydrodynamic Simulationsof the Interaction of Magnetic Flux Tubes Authors: Kondrashov, D.; Feynman, J.; Liewer, P. C.; Ruzmaikin, A. Bibcode: 1999ApJ...519..884K Altcode: We use a three-dimensional Cartesian resistive MHD code to investigate three-dimensional aspects of the interaction of magnetic flux tubes as observed in the solar atmosphere and studied in laboratory experiments. We present here the first results from modeling the reconnection of two Gold-Hoyle magnetic flux tubes that follow the system evolution to a final steady state. The energy evolution and reconnection rate for flux tubes with both parallel and antiparallel axial fields and with equal and nonequal strengths are studied. For the first time, we calculate a gauge-invariant relative magnetic helicity of the system and compare its evolution for all the above cases. We observed that the rate at which helicity is dissipated may vary significantly for different cases, and it may be comparable with the energy dissipation rate. The footpoints of the interacting flux tubes were held fixed or allowed to move to simulate different conditions in the solar photosphere. The cases with fixed footpoints had lower magnetic energy release and reached a steady state faster than cases with moving footpoints. For all computed cases the magnetic energy was released mostly through work done on the plasma by the electromagnetic forces rather than through resistive dissipation. The reconnection rate of the poloidal magnetic field is faster for the case with antiparallel flux tubes than for the case with parallel flux tubes, consistent with laboratory experiments. We find that during reconnection supersonic (but sub-Alfvénic) flows develop, and it may take a considerably longer time for the system to reach a steady state than for magnetic flux to reconnect. It is necessary to retain the pressure gradient in the momentum equation; the plasma pressure may be significant for the final equilibrium steady state even with low-β initial conditions, and the work done on the plasma by compression is important in energy exchange. Title: On generation of high-frequency Alfvén waves in the solar corona Authors: Ruzmaikin, Alexander; Berger, Mitchell A. Bibcode: 1999AIPC..471..325R Altcode: 1999sowi.conf..325R We discuss a source for high-frequency Alfvén waves, associated with twisted magnetic loops emerging on the solar surface and reconnecting with the open field. We identify the loops with the ephemeral regions (small-scale bipoles) observed by ground-based instruments and by SOHO. To characterize the loops we employ the concept of a minimum energy state for topologically complex fields. Our estimates of the power that can be released and the range of wave frequencies marginally agree with models of coronal heating and acceleration of the solar wind by high-frequency Alfvén waves. We suggest that severe requirements on the upper-bound frequency, used in these models, can be relaxed by taking into account the energy released due to reconnections within magnetic loops whose footpoints are twisted by surface convective motions. This presentation updates our more extended discussion of the source of coronal heating (1). Title: Sun-Earth Connection Observatory (SECO) Authors: Ruzmaikin, A. Bibcode: 1999AAS...194.7602R Altcode: 1999BAAS...31Q.956R To understand fundamentals of Sun-Earth Connections in general and Space Weather in particular, full-Sun viewing is required. A minimal mission includes simultaneous observations from behind the Sun and from the earthside. This mission will bring understanding of how geoeffective solar magnetic activity originates by: (1) following magnetic activity from its source in the solar interior to the solar surface using deep helioseismic probing, (2) continuously observing the solar surface development of sources of geoeffective (fast) CMEs and particle events using Doppler-magnetic imaging, (3) observing coronal magnetic fields using Faraday rotation measurements deconvolved by modeling with full-Sun boundary conditions obtained from imaging, (4) developing a capability for advanced space weather prediction with a lead time of days using measurements of solar energetic particles and magnetic fields simultaneously from both sides of the Sun. An extended, 4pi mission with additional spacecraft above the solar poles (solar sail required) will allow the viewing of the entire solar globe. This will combine the solar polar mission science goals (meridional flows, polar magnetic fields) with those of the above minimal mission, plus affording new synergistic opportunities such as interplay between active regions (latitude <45deg ) and polar structures (latitude >45deg ) and 3-D imaging of CMEs. Suggested instrumentation includes a Doppler-magnetograph for photospheric imaging, particle detectors and a magnetometer for in-situ measurements, and a two-frequency radio system (X and Ka bands) for communication and coronal sounding. Unique aspects and advantages of the concept for the NASA Road Map are discussed. Title: Anomalous Diffusion of Solar Magnetic Elements Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A. Bibcode: 1999AAS...194.5506C Altcode: 1999BAAS...31..911C The diffusion properties of photospheric bright points associated with magnetic elements (MBP's) in the granulation network are analyzed. We find that the transport is subdiffusive for times less than 20 minutes but normal for times larger than 25 minutes. The subdiffusive transport is caused by the walkers being trapped at stagnation points in the intercellular pattern. We find that the distribution of waiting times at the trap sites obeys a truncated Levy type (power law) distribution. The fractal dimension of the pattern of sites available to the random walk is less than 2 for the subdiffusive range and tends to 2 in the normal diffusion range. We show how the continuous time random walk formalism can give an analytical explanation of the observations. We simulate this random walk by using a version of a phenomenological model of renewing cells introduced originally for supergranules by Simon, Title and Weiss (1995). We find that the traps which cause the subdiffusive transport arise when the renewed convection cell pattern is neither fixed nor is it totally uncorrelated from the old pattern as required in Leighton's model, but in some intermediate state between these extremes. (Work supported in part by NSF grant ATM-9628882). Title: Scaling Universality Classes and Analysis of Solar Data Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1999AAS...194.9301L Altcode: 1999BAAS...31..988L Many solar phenomena display a scaling symmetry associated with random multiplicative cascades. Here a physical measure, initially uniform on a spatial, temporal, or space-time set, is divided among subsets according to randomly determined fractions. This division is repeated on smaller and smaller sub-subsets, so that the resulting measure at the smallest scale is given at any point by the product of a string of random fractions comprising its fragmentation history. Such measures are highly intermittent. They characterize such solar phenomena as the spatial distribution of magnetic flux in an active region and the time distribution of global X-ray emission. The probability distribution functions (PDFs) governing the random fractions fall into universality classes with robust properties (Hentschel 1994). For example, all PDFs which allow for zero fractions lead to measures with local peaks of unlimited strengths which are progressively less and less space filling. The GOES-2 X-ray data belong to this class, which indicates the presence of critical behavior associated with flares (Lu & Hamilton 1991). We investigate a number of time series for the presence or absence of this property. Multifractals in nature may fall into a narrow universality class described by just 3 parameters (Schertzer, et al. 1997). We find that at least some examples of active region magnetic fields do indeed have the conjectured form. Further, we apply a causal space-time version of this class of multiplicative cascade processes to forecasting the evolution of solar velocity fields. This work was supported in part by NSF grant ATM-9628882. Hentschel, H.G.E. 1994, Phys. Rev. E, 50, 243. Lu, E.T. & Hamilton, R.J. 1991, ApJ, 380, L89. Schertzer, D., Lovejoy, S., Schmitt, F., Chigirinskaya, Y. & Marsan, D. 1997, Fractals, 5, 427. Title: Characteristic Scales of Photospheric Flows and Their Magnetic and Temperature Markers Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1999ApJ...513..506L Altcode: We study the characteristic scales of quiet-Sun photospheric velocity fields along with their temperature and magnetic markers in Doppler images from the Michelson Doppler Imager aboard the SOHO satellite (SOHO/MDI) in simultaneous, Doppler, magnetic, and intensity images from the San Fernando Observatory and in full-disk magnetograms and an intensity image from National Solar Observatory (Kitt Peak). Wavelet flatness spectra show that velocity fluctuations are normally distributed (Gaussian). This is often assumed in stochastic models of turbulence but had not yet been verified observationally for the Sun. Temperature fluctuations also are Gaussian distributed, but magnetic fields are intermittent and are gathered into patterns related to flow structures. Wavelet basis functions designed to detect characteristic convection cell-flow topologies in acoustically filtered SOHO/MDI Doppler images reveal granulation scales of 0.7-2.2 Mm and supergranulation scales of 28-40 Mm. Mesogranular flows are weakly but significantly detected in the range 4-8 Mm. The systematic flows account for only 30% of the image variances at granular and supergranular scales and much less in between. The main flows for the intermediate range of 2-15 Mm are self-similar, i.e., chaotic or turbulent. Title: Can We Get the Bottom B? Authors: Ruzmaikin, Alexander Bibcode: 1999soho....9E..26R Altcode: Understanding the solar dynamics and the origin of active regions depends crucially on knowledge of magnetic fields in the convection zone. According to the SOHO/MDI results (Kosovichev et al. 1997) the dynamo generates magnetic fields mainly near the bottom of the convection zone. How can we get there? Some clues are given by dynamo theories, and modeling of instabilities in the convection zone and processes which result in the emergence of magnetic flux. Magnetic fields are believed to be generated in the form of predominantly azimuthal flux tubes. When the magnetic field strength exceeds some critical value, MHD instabilities break the azimuthal symmetry and lead to the formation of magnetic loops emerging as active regions at the solar photosphere. Simulations of instability and emergence include buoyancy, rotational, and curvature effects and permit prediction of some properties of the emerging magnetic loops. An example is the prediction of the distribution of emerging magnetic fields in solar longitude. Simulations by Caligari et al. (ApJ, 441, 886, 1995) indicate that the emergence of a certain azimuthal mode of magnetic field strongly depends on the field strength at the bottom of the convection zone. Hence identification of the longitudinal distribution of emerging photospheric magnetic fields can give us the information about the magnetic field strength at the bottom of the convection zone. Distinguishing between the modes of emerging field most probably requires simultaneous magnetic imaging of both sides of the Sun. Simultaneous Doppler imaging of the photosphere from earthside and from behind the Sun combined with the time-distance technique (Duvall et al., Nature, 362, 430, 1993) opens an opportunity to detect fine structures at the base of the convection zone, such as localized jets or magnetic-field-aligned temperature perturbations associated with originating active regions (Ruzmaikin et al. in Synoptic Physics, ed. by Balasubramaniam and Harvey, 1998). Title: Spatiotemporal Correlations and Turbulent Photospheric Flows from SOHO/MDI Velocity Data Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A.; Walton, S. R.; Tarbell, T. Bibcode: 1998ApJ...509..918C Altcode: Time series of high-resolution and full-disk velocity images obtained with the Michelson Doppler Imager (MDI) instrument on board SOHO have been used to calculate the spacetime spectrum of photospheric velocity flow. The effects of different methods for filtering acoustic oscillations have been carefully studied. It is found that the spectra show contributions both from organized structures that have their origin in the convection zone and from the turbulent flow. By considering time series of different duration and cadence in solar regions with different line-of-sight projections, it is possible to distinguish the contributions of the spectra from the two different kinds of flows. The spectra associated with the turbulent velocity fields obey power laws characterized by two scaling parameters whose values can be used to describe the type of diffusion. The first parameter is the spectral exponent of the spatial correlation function and the second is a scaling parameter of the time correlation function. Inclusion of the time parameter is an essential difference between the present work and other solar studies. Within the confidence limits of the data, the values of the two parameters indicate that the turbulent part of the flow in the scale range 16-120 Mm produces superdiffusive transport. Title: Compact Doppler magnetograph Authors: Ruzmaikin, Alexander; Moynihan, Philip I.; Vaughan, Arthur H.; Cacciani, Alessandro Bibcode: 1998SPIE.3442..115R Altcode: We designed a low-cost flight instrument that images the full solar disk through two narrow band filters at the red nd blue 'wings' of the solar potassium absorption line. The images are produced on a 1024 X 1024 charge-coupled device with a resolution of 2 arcsec per pixel. Four filtergrams taken in a very short time at both wings in the left and right states of circular polarization are used to yield a Dopplergram and a magnetogram simultaneously. The noise-equivalent velocity associated with each pixel is less than 3 m/s. The measured signal is linearly proportional to the velocity in the range +/- 4000 m/s. The range of magnetic fields is from 3 to 3000 Gauss. The optical system of the instrument is simple and easily aligned. With a pixel size of 12 micrometers , the effective focal length is 126 cm. A Raleigh resolution limit of 4 arcsec is achieved with a 5-cm entrance apertures, providing an f/25 focal ratio. The foreoptic is a two-component telephoto lens serving to limit the overall optical length to 89 cm or less. The mass of the instrument is 14 kg. the power required is less than 30 Watts. The Compact Doppler Magnetograph can be used in space mission with severe mass and power requirements. It can also be effectively used for ground-based observations: large telescope, dome or other observatory facilities are not required. Title: On a source of Alfven waves heating the solar corona Authors: Ruzmaikin, Alexander; Berger, Mitchell A. Bibcode: 1998A&A...337L...9R Altcode: Studies of the origin of coronal heating and acceleration of the solar wind invoke high-frequency Alfv{e}n waves. Here we suggest a source for such waves associated with twisted magnetic loops emerging on the solar surface and reconnecting with the open field. We identify the loops with the ephemeral regions (small-scale bipoles) observed by ground-based instruments and by SOHO. To characterize the loops we employ the concept of a minimum energy state for topologically complex fields. Emerging loops release energy relaxing to the minimum state. Relaxation along the minimum state-due to a competition between footpoint twisting by photospheric motions and reconnections inside the loops- releases blinks of energy into the solar atmosphere. We estimate the power released and the range of wave frequencies. Title: Clustering of Emerging Magnetic Flux Authors: Ruzmaikin, A. Bibcode: 1998SoPh..181....1R Altcode: Observations show that newly emerging flux tends to appear on the solar surface at sites where there is flux already; this results in clustering of solar activity. Standard dynamo theories do not predict this effect, and the mean field estimated by the theories is too weak to emerge at the surface of the Sun at all. Here a solution of the problem is suggested that involves strong fluctuating fields generated by the dynamo. The magnetic field emerges at the solar surface when the total field (the mean field plus fluctuations) exceeds the threshold for buoyancy. A slowly changing enhancement of the mean field provides a long-living basis ('hump') for emergence of fluctuating fields. The enhancements are gradually destroyed by the solar differential rotation, the stretching time scale of which defines the lifetime of clusters of activity. A simple 2-dimensional model explaining the appearance of persistent clusters of emerging flux is presented. Title: Transient solar influence on terrestrial temperature fluctuations Authors: Lawrence, J. K.; Ruzmaikin, A. A. Bibcode: 1998GeoRL..25..159L Altcode: We argue that the 11-year periodic solar cycle input assisted by intrinsic climatic noise can produce transient correlations between activity on the Sun and the Earth's temperature. The argument is based on wavelet analysis of simultaneous, 140-year time series of terrestrial global temperature and solar activity. It is supported by a simple model utilizing the concept of “stochastic resonance,” a unique effect of amplification of a weak, periodic signal by a noisy, nonlinear system. Title: Enhanced Synoptic Observations: A Spacecraft on the Other Side of the Sun Authors: Ruzmaikin, A.; Feynman, J.; Harvey, J.; Harvey, K.; Magsonas Team Bibcode: 1998ASPC..140..553R Altcode: 1998ssp..conf..553R No abstract at ADS Title: Turbulence in coronal mass ejections Authors: Ruzmaikin, A.; Feynman, J.; Smith, E. J. Bibcode: 1997JGR...10219753R Altcode: The magnetic fields measured by the ISEE 3 spacecraft are used to study MHD turbulence within coronal mass ejections (CMEs). The spectral indices of the turbulence inside CMEs are compared with spectral indices found in solar wind undisturbed by CMEs. Irrespective of the CME velocities, the spectra within CMEs are found to differ from those determined for the fast solar wind from coronal holes. Instead, the CME spectra more closely resemble those found in the slow solar wind. Since both CMEs and the plasma sheet are associated with closed magnetic structures in the solar corona, it appears that the turbulence in the solar wind arising from closed coronal regions is fundamentally different from the turbulence in wind from coronal holes. Helical properties of magnetic fields within CMEs at different scales are studied. Preliminary results indicate that, in small scales, helical fields are distributed in a random fashion with alternating signs of twisting structures. In addition however, CMEs have largescale helical structures. In the case of the magnetic cloud of day 302, 1978 this structure is interpreted as a part of the helical structure identified previously by fitting the data to a force-free flux rope configuration. Title: A model of diffusion produced by a cellular surface flow Authors: Ruzmaikin, Alexander; Molchanov, Stanislav A. Bibcode: 1997SoPh..173..223R Altcode: A model of diffusion induced by the joint action of random cells of two different sizes (granulation and supergranulation) is developed. The basic properties of the model are defined by the dimensionless ratio ζ = (the life time)/(characteristic size/velocity) constructed for these two types of cells. An analytical expression for the diffusivity as a function of ζ is derived. It is estimated that for the standard parameters used the contribution of granulation to the joint diffusion is small. A comparison between the model and numerical simulations of the kinematic diffusion of magnetic fields on the solar surface is made. Title: Scale Dependence of Photospheric Magnetic, Velocity and Temperature Structure Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1997SPD....28.0247L Altcode: 1997BAAS...29..901L Time series fluctuations may show different structure when observed at different time scale resolutions. Thus, wavelet analysis reveals that fluctuations in the International Sunspot Number are intermittent (that is, distributed with kurtosis K>0) on scales less than 2 yr, but truncated (K<0) on time scales between 2-8 yr. Terrestrial temperature fluctuations are normally distributed (K=0) over discrete timescale bands (<1 yr, 4-6 yr, 13 yr) interspersed by regimes of intermittence (1-4 yr) and truncation (6-13 yr). Similar effects occur for spatial phenomena. We employ various continuous, two-dimensional wavelets to analyze digital solar images in Cartesian projection (simultaneous, co-registered San Fernando Observatory magnetic, Doppler and continuum images; SOHO/MDI high resolution Doppler images) and full-disk images in hemispheric projection (KPNO magnetograms, SOHO/MDI Doppler images). The temperature and velocity data are normally distributed at all scales up to 64 arc sec, though the temperature gradients are slightly intermittent (K~1). The magnetic data are mostly intermittent. Wavelet power spectra for KPNO full-disk magnetograms are quite featureless and indicate scale invariance of the magnetic structures. Structural spectra of both active and quiet sun images, however, show a strong peak in intermittence at a scale near 8 arc sec. Wavelet analysis permits localization of structures in space as well as in spatial scale. The highly intermittent structures can be mapped and are found to be located not in active regions but in some, though not all, areas of low magnetic activity. We discuss possible physical relationships among the magnetic, velocity and temperature distributions studied. Title: Decorrelation Time of Fourier modes in the Spectrum of Solar Background Velocity Fields Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A. Bibcode: 1997SPD....28.0261C Altcode: 1997BAAS...29..904C We calculate the power-energy spectrum of time series of SOHO/MDI line-of sight high resolution Doppler images near disk center. While the spatial spectrum presents velocity features at characteristic scales and not a cascade in wavenumber space, we investigate the extent to which it is still possible to describe in terms of a scaling exponent the properties of the decorrelation time for each Fourier mode as a function of wavelength. We explore the sensitivity of the result to different methods for removing the contribution of the p-modes to the spectrum. Title: On the origin of sunspots. Authors: Ruzmaikin, A. Bibcode: 1997A&A...319L..13R Altcode: It is proposed that sunspots (and other flux emergence phenomena) originate due to the presence of fluctuating magnetic fields in addition to the regular, mean field in the convection zone. The mean field predicted by dynamo theories is too weak by itself to emerge at the surface of the Sun. However, the same dynamo processes that produce the mean field also produce fluctuating fields. It is suggested here that magnetic fields emerge at the solar surface at those random times and places when the total magnetic field (mean field plus fluctuations) exceeds the threshold for buoyancy. In this way the mean field is responsible for observed regularities of the sunspot magnetic fields, such as the Hale's law and the 11-year periodicity, and the fluctuations are responsible for emergence of the magnetic field of individual sunspots. A simple illustrative model calculation of a series of "sunspot cycles" is presented. The model spectrum compares well with the observed spectrum of sunspots. Title: Wavelet analysis of the structure of microstreams in the polar solar wind Authors: Neugebauer, M.; Ruzmaikin, A.; McComas, D. J. Bibcode: 1997AIPC..385...41N Altcode: 1997recs.conf...41N The fluctuations in solar-wind velocity measured by the Ulysses spacecraft above the polar regions of the Sun are organized into structures called microstreams. The application of wavelet transformations to the Ulysses data reveals the scales and positions of the microstreams and their association with variations in the helium content of the solar wind. It is concluded that the microstreams must have their origin in solar structures associated with the acceleration of the solar wind with little modification resulting from interplanetary phenomena. Title: Wavelet and Multifractal Analyses of Spatial and Temporal Solar Activity Variations Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1997scma.conf..421L Altcode: No abstract at ADS Title: A Spacecraft Going Behind the Sun Will Support SOHO Authors: Ruzmaikin, A.; Anderson, J. D.; Asmar, S.; Bird, M.; Cassiani, A.; Coles, W.; Feynman, J.; Harvey, J.; Harvey, K.; Hollweg, J.; Linker, K.; Mikic, Z.; Pätzold, M.; Smith, E. J. Bibcode: 1997ESASP.404..653R Altcode: 1997cswn.conf..653R No abstract at ADS Title: Spectral Properties of Solar Convection and Diffusion Authors: Ruzmaikin, A. A.; Cadavid, A. C.; Chapman, G. A.; Lawrence, J. K.; Walton, S. R. Bibcode: 1996ApJ...471.1022R Altcode: We present the results of a study of the scaling properties of solar photo spheric motions. We use time series of Doppler images obtained in good seeing conditions with the San Fernando Observatory 28 cm vacuum telescope and vacuum spectroheliograph in video spectra-spectroheliograph mode. Sixty line-of- sight Doppler images of an area of the quiet Sun near disk center are investigated. They were taken at 60 s intervals over a 1 hr time span at ∼2" resolution.

After filtering to remove 5 minute acoustic oscillations, the time-spatial spectrum of the velocity is calculated. To study the turbulence of photospheric flows in the mesogranulation scale range, we estimate two scaling parameters in the spectrum: the exponent of the spatial part of the power spectrum and the exponent governing the scaling of time correlations of each spatial mode. These parameters characterize the type of diffusion involved and the fractal dimension of the diffusion front. Our results indicate that the turbulent diffusion produced by motions in this scale range is not normal diffusion but superdiffusion. Title: Redistribution of magnetic helicity at the Sun Authors: Ruzmaikin, A. A. Bibcode: 1996GeoRL..23.2649R Altcode: Evolution of magnetic loops associated with filaments and coronal mass ejections involves a redistribution of solar magnetic helicity. Two mechanisms of the helicity redistribution are discussed. The first one involves magnetic reconnections among magnetic loops and can introduce helicity into an erupting magnetic field accompanied with an encapture of helicity by the Sun. The second one involves the MHD helicity redistribution in the Sun and indicates that the magnetic helicity of each hemisphere of the Sun oscillates about a mean with the half-period of the solar cycle (11 years), but does not change sign from one 11 year period to the next. Title: On the Multifractal Distribution of Solar Magnetic Fields: Erratum Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1996ApJ...467..473L Altcode: Many studies have pointed out fractal and multifractal properties of photospheric magnetic fields, but placing the various approaches into context has proved difficult. Although fractal quantities are defined mathematically in the asymptotic limit of infinite resolution, real data cannot approach this limit. Instead, one must compute fractal dimensions or multifractal spectra within a limited range at finite scales. The consequent effects of this are explored by calculation of fractal quantities in finite images generated from analytically known measures and also from solar data. We find that theorems relating asymptotic quantities need not hold for their finite counterparts, that different definitions of fractal dimension that merge asymptotically give different values at finite scales, and that apparently elementary calculations of dimensions of simple fractals can lead to incorrect results. We examine the limits of accuracy of multifractal spectra from finite data and point out that a recent criticism of one approach to such problems is incorrect. Title: On the Multifractal Distribution of Solar Magnetic Fields Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1996ApJ...465..425L Altcode: Many studies have pointed out fractal and multifractal properties of photospheric magnetic fields, but placing the various approaches into context has proved difficult. Although fractal quantities are defined mathematically in the asymptotic limit of infinite resolution, real data cannot approach this limit. Instead, one must compute fractal dimensions or multifractal spectra within a limited range at finite scales. The consequent effects of this are explored by calculation of fractal quantities in finite images generated from analytically known measures and also from solar data. We find that theorems relating asymptotic quantities need not hold for their finite counterparts, that different definitions of fractal dimension that merge asymptotically give different values at finite scales, and that apparently elementary calculations of dimensions of simple fractals can lead to incorrect results. We examine the limits of accuracy of multifractal spectra from finite data and point out that a recent criticism of one approach to such problems is incorrect. Title: On the origin of the 1/f spectrum of fluctuations in the solar wind Authors: Ruzmaikin, A. A.; Goldstein, B. E.; Smith, E. J.; Balogh, A. Bibcode: 1996AIPC..382..225R Altcode: The origin of the 1/f low-frequency spectrum of fluctuations observed in the solar wind is discussed. It is suggested that this spectrum arises due to sampling random perturbations produced at the Sun. The perturbation process is characterized by a power-law distribution. It is pointed out that, due to solar rotation, the sampling is equivalent to scanning across different size scales on the Sun. The limits of the spectrum found from the observations are used to estimate the characteristic scales on the Sun, the scales related to the origin of the solar wind. Title: Radial evolution of the high/low frequency breakpoint in magnetic field spectra Authors: Feynman, J.; Ruzmaikin, A. A.; Smith, E. J. Bibcode: 1996AIPC..382..347F Altcode: Power spectra of magnetic field variations show different behavior in two frequency regions; a high frequency region (f-5/3) and a low frequency region (f-1). A clue to the relationship between them is in the behavior of the breakpoint between the spectral regions. Statistical studies of the average behavior of spectra between 0.3 AU and 22 AU have shown that the breakpoint occurs at lower frequencies with larger heliocentric distances. Ideally the behavior of the breakpoint in a particular parcel of solar wind should be studied as that parcel propagates to larger heliocentric distances. The possibility of carrying out such a study is provided by the fact that in 1974 IMP 8 (1.0 AU), Pioneer 10 (4.3 AU) and Pioneer 11 (5.6 AU) were close to being coaligned. We compare the breakpoint observed at Earth with that observed at Pioneers 10 and 11 for closely matched samples of the wind and find good agreement with a model in which the high frequency spectrum develops in interplanetary space through a cascade from the low frequency spectrum. Title: Spectral Properties of the Solar Background Velocity Field Authors: Cadavid, A. C.; Chapman, G. A.; Lawrence, J. K.; Ruzmaikin, A. A.; Walton, S. R. Bibcode: 1996AAS...188.3506C Altcode: 1996BAAS...28Q.872C We study the scaling properties of time series of Doppler images obtained in good seeing conditions with the San Fernando Observatory 28 cm vacuum telescope and vacuum spectroheliograph in video spectra-spectroheliograph mode. The images correspond to two areas of quiet Sun near disk center taken at 60 second intervals from one hour to six hour spans at ~ 2 arcsec resolution. After removal of 5 min acoustic oscillations the time-spatial spectrum of the velocity is calculated. To study the turbulence of photospheric flows we estimate two scaling parameters: the exponent of the spatial part of the power spectrum and the exponent governing the scaling of time correlations of each spatial mode. The implied diffusive behavior produced by the solar convection in the mesogranulation scale range is discussed. This includes characterization of the type of diffusion involved and the fractal dimension of the diffusion front. Title: Magnetic field asymptotics in a well conducting fluid Authors: Dobrokhotov, Sergei; Olive, Victor M.; Ruzmaikin, Alexander; Shafarevich, Andrei Bibcode: 1996GApFD..82..255D Altcode: An asymptotic solution of the magnetic induction equation in a given velocity field is constructed for large magnetic Reynolds numbers. Initially localized distributions of the magnetic field are considered. The leading term of the asymptotics is found. The expansions are proved to be rigorously valid over a finite time interval. Estimates for the residuals are given. The results are illustrated by some examples: the Hubble flow with a linear dependence of the velocity on coordinates, and ABC type flows. The solutions in these cases are expressed in terms of elementary functions. Title: Turbulent and Chaotic Dynamics Underlying Solar Magnetic Variability Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1995ApJ...455..366L Altcode: We examine the temporal scaling properties of solar magnetic activity on timescales from days to decades. Because of more than 63,000 usable data points, we concentrate on the daily International Sunspot Number. Some results have been checked with other data sets, primarily the 10.7 cm microwave flux with about 16,000 data points. Such time series provide a measure whose scaling and intermittency properties are analyzed.

By means of correlation analysis and both Fourier and wavelet spectral analysis, we distinguish two regimes of temporal behavior of the magnetic variability. The scaling of the time series is analyzed in terms of multiplicative cascade processes which prove to be invariant over more than two decades of scale from about 2 yr down to about 2 days or less. We interpret this result to indicate generic turbulent structuring of the magnetic fields as they rise through the convection zone. We find that a low-dimensional, chaotic behavior in the sunspot number operates entirely at timescales longer than a transition threshold scale of about 8 yr. Magnetic variability on timescales between 2 yr and 8 yr apparently requires handling by direct simulation. Title: Features of the Solar Background Velocity Field Authors: Ruzmaikin, A.; Cadavid, C.; Chanpman, G.; Lawrence, J.; Walton, S. Bibcode: 1995ESASP.376b.249R Altcode: 1995help.confP.249R; 1995soho....2..249R No abstract at ADS Title: On the origin of 1/f spectrum of magnetic fluctuations in the solar wind Authors: Ruzmaikin, A.; Goldstein, B. E.; Smith, E. J.; Balough, A. Bibcode: 1995sowi.conf...38R Altcode: Spacecraft measurements show that the spectrum of magnetic fluctuations in the solar wind can be divided into low- and high frequency parts. The low and high frequency parts are approximately self-similar (follow a power-law) but with different spectral exponents. (There is, in addition, a very low frequency range in which the spectrum is dominated by structures coming directly from the Sun and it is not self-similar.) For the wind coming from the south polar hole the boundary between the low- and high frequency parts is at about 1 hour near 1 AU. The observed exponent of the low-frequency part is approximately -1 . The high frequency spectrum is steeper with an exponent of about -5/3 . The high frequency spectrum is commonly believed to be the result of non-linear interactions of magnetic and velocity perturbations which lead to a turbulent cascade. However, for the low frequency fluctuations, the site of origin (on the Sun, in the solar corona or in the solar wind?) and mechanism of generation remain basically unknown. In this paper we consider the origin of the 1/f spectrum. The analysis of Ulysses data is compared with analysis of Helios data and the results are used to confront possible models of origin of the spectrum. Title: Radial evolution of the high/low frequency breakpoint in magnetic field spectra Authors: Feynman, J.; Ruzmaikin, A.; Smith, E. J. Bibcode: 1995sowi.conf...80F Altcode: The spectra of magnetic field variations in the solar wind show different behavior in two frequency regions; a high frequency region in which the spectral exponent is about -5/3 and a low frequency region in which it is typically -1. The two types of variations must arise from different processes and a clue to the relationship between the spectral regions lies in understanding the behavior of the breakpoint between the spectral regions. Studies of the average behavior of spectra have shown that the break point occurs at about 3.5 hours at 1 AU. It is also known that, on average, the breakpoint occurs at lower frequencies with larger heliocentric distances. Ideally however, instead of the average properties of the spectra, we would like to know how the breakpoint evolves in particular samples of the solar wind as they propagate to larger heliocentric distances. In the study reported here we take advantage of the fact that, in 1974, Pioneer 10 (4.4 AU) and Pioneer 11 (5.6 AU) were close to being co-aligned and being aligned with the Earth. Solar wind observed at Earth can be closely matched with solar wind later observed at P10 and P11. We here compare the breakpoint observed at Earth with that observed at Pioneers 10 and 11 for matched samples of the wind. Title: Magnitude of the dynamo-generated magnetic field in solar-type convective zones. Authors: Kleeorin, N.; Rogachevskii, I.; Ruzmaikin, A. Bibcode: 1995A&A...297..159K Altcode: Using a nonlinear dynamo model (in a single-mode approximation), an analytical expression is derived which gives the magnitude of the mean magnetic field as a function of rotation and other parameters for a solar-type convective zone. By means of this expression we find a power-law relation between the X-ray luminosity and stellar rotation. The exponent in this relation is in agreement with observations. Title: Turbulence and Chaos in Solar Variability Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A. Bibcode: 1995SPD....26..514C Altcode: 1995BAAS...27..960C No abstract at ADS Title: Intermittent turbulence in solar wind from the south polar hole Authors: Ruzmaikin, A. A.; Feynman, J.; Goldstein, B. E.; Smith, E. J.; Balogh, A. Bibcode: 1995JGR...100.3395R Altcode: The magnetic fields measured by the Ulysses spacecraft are used to study solar wind turbulence in the fast solar wind from the south polar hole. The spacecraft was at about 46 deg south latitude and 3.9 AU. For a magnetic field with a Gaussian distribution the power spectrum (second-order structure function) is sufficient to completely characterize the turbulence. However, the actual distribution is non-Gaussian so that the effects of intermittency must be taken into account. The observed spectral exponents include effects of intermittency and cannot be directly compared with the standard second-order spectral theories such as the Kolmogorov and Kraichnan theories. To permit a better comparison of the observations with the theoretical models, we study the structure characteristics of the data. We find the exponents of the second-order structure functions (power spectra) and the higher-order normalized structure functions for the components of the magnetic fields. We show that these sets of exponents can be approximately described by two basic numbers: the spectral exponent and the intermittency exponent. The intermittency exponent characterizes correlation properties of the energy cascade from large to small scales. Before comparing the observations to the theoretically expected values, a reduction must be made to the observed spectral exponent. The amount of the reduction depends on both the intermittency exponent and the model of the energy cascade assumed in the turbulence theory. We reduce the measured spectral indices according to a simple model for Alfvén turbulence that is described here. We then compare our reduced spectral indices with second-order spectral theory. The reduced spectral indices for the period range of 1 min to about a half hour are remarkably constant and in good agreement with the value of 3/2. Thus our treatment is self-consistent. Our tentative conclusion is that the high-frequency turbulence appears to agree with the model of random-phased Alfvén waves. This tentative conclusion must be tested by further theoretical and observational work. Title: Multiplicative cascade models of multifractal solar magnetic fields Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1995PhRvE..51..316L Altcode: We present a multifractal analysis of digital, photoelectric images of line-of-sight magnetic fields in solar active regions and quiet photosphere. We study a positive definite measure related to the Ohmic dissipation of magnetic energy. After calculation of the multifractal spectrum directly and by scaling of the moments of the measure, we focus on a multiplicative cascade approach. We infer a scale-invariant rule by which the Ohmic dissipation measure is allocated among subsets of its support through a hierarchy of scales. Knowledge of this rule, which is hampered to some extent by image noise, permits the calculation of the multifractal spectrum to great accuracy. The scaling of the solar dissipation field resembles that of fully developed turbulence in an atmospheric boundary layer. The cascade multiplier probability distribution is itself a very useful quantity. It allows a convenient display of image properties, such as self-similarity. Further, it is more closely related than the multifractal spectrum to the physics of the turbulent field evolution, and it thus can be used to impose stronger constraints on turbulent dynamo models of magnetic field generation. Title: Spectra of Solar Magnetic Fields and Diffusion Authors: Ruzmaikin, A. A.; Cadavid, A. C.; Chapman, G. A.; Lawrence, J. K.; Walton, S. R. Bibcode: 1995ASPC...76..292R Altcode: 1995gong.conf..292R No abstract at ADS Title: Scaling of Solar Magnetic Fields Authors: Ruzmaikin, A.; Cadavid, C.; Lawrence, J.; Rabin, D.; Lin, H. -S. Bibcode: 1995itsa.conf..375R Altcode: No abstract at ADS Title: Solar irradiance variations and nonlinear mean field dynamo Authors: Kleeorin, N.; Rogachevskii, I.; Ruzmaikin, A. Bibcode: 1994SoPh..155..223K Altcode: By using a nonlinear model of an axisymmetricα - Ω dynamo, an analytical expression which gives the magnitude of the mean magnetic field as a function of rotation and other parameters for a solar-type convective zone is obtained. The mean magnetic field varies as the power of the rotation rate. The resulting theoretical relationship of the X-ray luminosity as a function of the angular velocity is in agreement with observations by Fleming, Gioia, and Maccacaro (1989). Title: Distribution of the interplanetary magnetic field revisited Authors: Feynman, Joan; Ruzmaikin, Alexander Bibcode: 1994JGR....9917645F Altcode: The adequacy of the power spectrum to characterize the variations of a parameter depends on whether or not the parameter has a Gaussian distribution. We here perform very simple tests of Gaussianity on the distributions of the magnitudes of the interplanetary magnetic field, and on the distributions of the components; that is, we find the first four cumulants of the distributions (mean, variance, skewness, and kurtosis) and their solar cycle variations. We find, consistent with other recent analyses, that the traditional distributions of the 1-hour averaged magnitude are not distributed normally or lognormally as has often been assumed and the 1-hour averaged z component is found to have a nonzero kurtosis. Thus the power spectrum is insufficient to completely characterize these variations and polyspectra are needed. We have isolated variations in the 1/f frequency region of the spectrum and show that the distributions of the magnitudes have nonzero skewness and kurtosis, the magnitudes are not distributed lognormally, and the distributions of the components have nonzero kurtosis. Thus higher-order spectra are again needed for a full characterization. Title: Multifractal Models of Small-Scale Solar Magnetic Fields Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A.; Kayleng-Knight, A. Bibcode: 1994ApJ...429..391C Altcode: We generate, both analytically and numerically, artifical, two-dimensional images composed of a known self-similar, and thus multifractal measured with added Gaussian white noise. These are used to interpret observed, line-of-sight, solar magnetic field distributions noisy multifractals. The range of self-similar scaling of observed, distributions is extended beyond that of previous work. Our interpretation of the data is then used to confront theoretical models for the generation of small-scale solar magnetic fields. We investigate the multifractial structure of the field generated by two-dimensional, random cell dynamos and find that self-similarity is relatively enhanced for more intermittent distributions and strong correlations between cells. An optimum value of the intercellular diffusion coefficient maximizes the degree of intermittency. The simulated field from a linear, kinematic, fast dynamo with two-dimensional, chaotic, 'ABC' flow displays scaling properties resembling those of observed solar fields. We suggest that the chaotic element of this model is the crucial ingredient for the long-range correlations that lead to multifractal scaling. Title: Long-term persistence of solar activity Authors: Ruzmaikin, Alexander; Feynman, Joan; Robinson, Paul Bibcode: 1994SoPh..152..313R Altcode: 1994IAUCo.143..313R; 1994svs..coll..313R The solar irradiante has been found to change by 0.1% over the recent solar cycle. A change of irradiante of about 0.5% is required to effect the Earth's climate. How frequently can a variation of this size be expected? Title: Long-term persistence of solar activity Authors: Ruzmaikin, Alexander; Feynman, Joan; Robinson, Paul Bibcode: 1994SoPh..149..395R Altcode: We examine the question of whether or not the non-periodic variations in solar activity are caused by a white-noise, random process. The Hurst exponent, which characterizes the persistence of a time series, is evaluated for the series of14C data for the time interval from about 6000 BC to 1950 AD. We find a constant Hurst exponent, suggesting that solar activity in the frequency range from 100 to 3000 years includes an important continuum component in addition to the well-known periodic variations. The value we calculate,H ≈ 0.8, is significantly larger than the value of 0.5 that would correspond to variations produced by a white-noise process. This value is in good agreement with the results for the monthly sunspot data reported elsewhere, indicating that the physics that produces the continuum is a correlated random process and that it is the same type of process over a wide range of time interval lengths. Title: Scaling properties of photospheric magnetic fields Authors: Lawrence, J. K.; Cadavid, A. C.; Ruzmaikin, A. A. Bibcode: 1994ASIC..433..279L Altcode: No abstract at ADS Title: Multifractal Measure of the Solar Magnetic Field Authors: Lawrence, J. K.; Ruzmaikin, A. A.; Cadavid, A. C. Bibcode: 1993ApJ...417..805L Altcode: We analyze high-resolution, digital, photoelectric images of solar photospheric magnetic fields. The line-of-sight fields are found to scale in a self-similar way with resolution and thus can be expressed in the form of a signed multifractal measure. The scaling properties of the measure are used to extrapolate field integrals, such as moments of the magnetic field, below resolvable limits. The scaling of the field moments is characteristic of highly intermittent fields. We suggest that the quiet-Sun photospheric fields are generated by local dynamo action based on random convective motions at high magnetic Reynolds number. The properties of active region images are determined by the presence of fields generated by the global, mean field dynamo. Title: The spectrum of the interplanetary magnetic field near 1.3 AU Authors: Ruzmaikin, Alexander; Lyannaya, I. P.; Styashkin, Valerij A.; Eroshenko, E. Bibcode: 1993JGR....9813303R Altcode: A time series of the interplanetary magnetic field measured near 1.3 AU by Phobos 2 is analyzed as a fractal. The fractal dimension of the curves corresponding to the components and to the strength of the magnetic field are found to be close to 5/3. The corresponding spatial spectra are interpreted in the framework of MHD turbulence. Title: Self-Similarity in Solar Magnetic Images Authors: Lawrence, J. K.; Ruzmaikin, A. A.; Cadavid, A. C. Bibcode: 1993BAAS...25.1219L Altcode: No abstract at ADS Title: Multiscale Measure of the Solar Magnetic Field Authors: Ruzmaikin, A. A.; Lawrence, J. K.; Cadavid, A. C. Bibcode: 1993BAAS...25.1219R Altcode: No abstract at ADS Title: Solar Magnetic Fields, Multifractals and Dynamos Authors: Cadavid, A. C.; Lawrence, J. K.; Ruzmaikin, A. A.; Kayleng-Knight, A. Bibcode: 1993BAAS...25R1206C Altcode: No abstract at ADS Title: Ekman-Hartmann Boundary Layers and the Length of Day Variations Authors: Kleeorin, N.; Rogachevskii, I.; Ruzmaikin, A. Bibcode: 1993IAUS..157..453K Altcode: No abstract at ADS Title: Random cell dynamo Authors: Ruzmaikin, Alexander; Liewer, Paulett C.; Feynman, Joan Bibcode: 1993GApFD..73..163R Altcode: A simple numerical model of the self-excitation of the magnetic field by chaotic motion of a highly conductive fluid is being developed. It is based on the following approach to simulating the turbulent dynamo generation of magnetic fields: the fluid is divided into cells and each cell acts as a machine that can randomly amplify or destroy a given magnetic field. The random amplification models the effects of a chaotic fast dynamo and the random destruction models the effects of reconnection. Uncorrelated and correlated processes are considered. Effects of non-linearity, diffusion, and correlation between cells in time and space are also included. Numerical results are presented from one- and two-dimensional models and possible applications to the generation and spatial-temporal distribution of solar, planetary and interplanetary magnetic fields are discussed. Title: On the role of rotation of the internal core relative to the mantle. Authors: Ruzmaikin, A. Bibcode: 1993spd..conf..265R Altcode: No abstract at ADS Title: Magnetic ropes in the solar wind Authors: Ruzmaikin, Alexander; Shukurov, Anvar; Sokolov, Dmitrii Bibcode: 1992JGR....9715007R Altcode: The generation of magnetic fluctuations by MHD turbulence in the solar wind is discussed. An estimate of the effective magnetic Reynolds number in the solar wind based on a width of the inertial range of the turbulence is proposed. Dynamo activity is predicted to lead to generation of magnetic ropes whose length is of the order of the energy range scale, 2.5×1011 cm, and whose thickness can be as low as 5×108 cm. Experimental detection of the ropes would require determination of two-point and higher correlation functions for the magnetic fluctuations in the solar wind. Title: Differential rotation of the liquid core of the Earth. Authors: Nikitina, L. V.; Ruzmaikin, A. A. Bibcode: 1992Ge&Ae..32..140N Altcode: Conditions for the appearance of anisotropic convection (a possible cause of the differential rotation of the earth's liquid core) are examined, and its parameters for the earth's core are determined. The distribution of the differential rotation is obtained, and the relative gradient of the angular velocities of the core and the mantle produced by the anisotropic convection is determined. The magnitude of this gradient is of the order of 10 exp -6, which is comparable with the western-drift velocity of the geomagnetic field. Title: Magnetic Intermittency on the Sun Authors: Ruzmaikin, Alexander Bibcode: 1992ASPC...27..189R Altcode: 1992socy.work..189R No abstract at ADS Title: On Long-Term Dynamics of the Solar Cycle Authors: Ruzmaikin, Alexander; Feynman, Joan; Kosacheva, Valentina Bibcode: 1992ASPC...27..547R Altcode: 1992socy.work..547R No abstract at ADS Title: On the origin of Uranus and Neptune magnetic fields Authors: Ruzmaikin, A. A.; Starchenko, S. V. Bibcode: 1991Icar...93...82R Altcode: The Uranus and Neptune magnetic fields discovered by Voyager 2 can be explained by a dynamo acting in a thin conductive convective shell existing at the bottom of the icy oceans of the planets. The main helicity and differential rotation are the source for the dynamo which effectively excites nonaxisymmetric modes of the mean magnetic field. Estimates of the magnetic field amplitude in the nonlinear regime and of the inclination between the magnetic moment and the rotation axis are given. Title: Measurement of the magnetic field vector from a rotating spacecraft. Authors: Trubetskov, M. K.; Eroshenko, E. G.; Liannaia, I. P.; Ruzmaikin, A. A.; Sokolov, D. D.; Stiazhkin, V. A.; Shukurov, A. M. Bibcode: 1991KosIs..29..597T Altcode: 1991CosRe..29..597T The authors propose a method of restoration of magnetic field components measured by a vector magnetometer onboard of a spacecraft which rotates at an angular velocity unknown in advance. The available magnetometer data are used for a precise estimation of the spacecraft angular velocity. The latter estimate, combined with knowledge of the initial orientation of the spacecraft, allows to restore the components of the external magnetic field in an inertial frame. The proposed method is applied to analysis of magnetic field measurements near Mars by "Phobos 2". The angular velocity of the spacecraft is estimated to an accuracy higher than 0.1 percent. Title: The Martian dynamo Authors: Ruzmaikin, Alexander Bibcode: 1991PEPI...67..268R Altcode: Mars has a well-conducting core composed of a mixture of iron and sulphur. It is probably liquid and differentially rotating. The main problem is whether the core is stably stratified or convective. About 10-15% of sulphur is enough to drive a compositional convection over a great part of Martian evolution if an inner solid solid core was formed. Convection in a liquid rotating stratified core results in a mean helicity, which, together with differential rotation and turbulent magnetic diffusivity, is a source for mean field dynamo. The magnitude of the magnetic field generated can explain the origin of magnetization of the shergottie, nakhlite and chassignite meteorites. However, the dynamo probably does not work at present, in accordance with a weak large-scale magnetic field on the Martian surface estimated from the Mars-2, -3, -5, and Phobos mission results. This field is interpreted as an external product of the magnetized mantle having a slightly elliptical form. Some other possible explanations for the outer magnetic field are discussed. Title: Large-scale flows excited by magnetic fields in the solar convective zone Authors: Kleeorin, N. I.; Ruzmaikin, A. A. Bibcode: 1991SoPh..131..211K Altcode: Observations demonstrate a nearly 22-year periodic zonal flow superimposed on general solar differential rotation (LaBonte and Howard, 1982) and some meridional motions (e.g., Tuominen, Tuominen, and Kyrolänen, 1983). Such flows can be excited by the magnetic wave generated by the dynamo in the solar convective zone. Title: The Toroidal Magnetic Field Inside the Sun Authors: Krivodubskij, V. N.; Dudorov, A. E.; Ruzmaikin, A. A.; Ruzmaikina, T. V. Bibcode: 1991LNP...380..187K Altcode: 1991IAUCo.130..187K; 1991sacs.coll..187K No abstract at ADS Title: Fractal Flux Tubes of the Solar Magnetic Field Authors: Ruzmaikin, Alexander; Sokoloff, Dmitry; Tarbell, Theodore Bibcode: 1991LNP...380..140R Altcode: 1991IAUCo.130..140R; 1991sacs.coll..140R The small-scale solar magnetic field exceeding a given threshold forms a fractal set. A dimension of this fractal is found from magnetograms with varying linear resolution. The dimension depends on the value of the threshold magnetic field (multifractality). A simple dynamo model explaining the origin of the fractal magnetic structure is considered. The dynamo produces a magnetic field in the form of flux tubes with a fractal distribution of magnetic field across the tube. The observed dimension gives a possibility of estimating a degree of structuredness of the solar velocity field. Title: Magnetic History of the Sun Authors: Levy, E. H.; Ruzmaikin, A. A.; Ruzmaikina, T. V. Bibcode: 1991suti.conf..589L Altcode: This review gives a brief overview of the major magnetic effects and behavior that characterized and influenced aspects of the gross history of the sun. The chapter surveys the behavior of magnetic fields in the sun from the early effect of the interstellar field on protosolar collapse through to the modern solar magnetic cycle. Emphasis is given to the evolution of the sun's magnetic field, its memory of the past magnetic states, and its loss of memory, as these depend on physical episodes, conditions and phenomena during the sun's development. Title: Asymptotic Methods in the Nonlinear Mean-Field Dynamo Authors: Sokoloff, D. D.; Shukurov, A.; Ruzmaikin, A. A. Bibcode: 1991LNP...380..135S Altcode: 1991IAUCo.130..135S; 1991sacs.coll..135S We discuss the methods and results of analysis of nonlinear mean-field dynamo models based on a-quenching in two asymptotic regimes, namely for weakly and highly supercritical excitation. In the former case the spatial distribution of the steady-state magnetic field is close to that given by the neutrally stable eigenfunction of the corresponding kinematic dynamo. In the latter case the magnetic field distribution within the main part of the dynamo volume is presumably determined by the balance between the Lorentz and Coriolis forces while near the boundaries boundary layers arise in which the field adjusts itself to the boundary conditions. The asymptotic behaviour of the highly supercritical aw-dynamos is sensitive to the particular form of dependence of the mean helicity on magnetic field while 2-dynamos are less sensitive to this dependence. Title: Azimuthal modes of the geomagnetic field. Authors: Ruzmaikin, A. A.; Tiurmina, L. O. Bibcode: 1990Ge&Ae..30.1022R Altcode: The concept of the energy spectrum of azimuthal modes (or m-modes) is introduced. The latitudinal amplitude distribution of the m-modes on the earth's surface is determined along with their asymmetry with respect to the equator; the mode with m greater than 2 is susbtantially weaker in amplitude than the principal modes, m = 0, 1, 2. A comparison of radial spectral distributions of the n and m modes indicates that determinations of the depth of a geomagnetic-field source using the 'white noise' concept are inadequate. Title: Book-Review - the Almighty Chance Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1990Sci...249R.573Z Altcode: No abstract at ADS Title: The Almighty Chance Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1990Sci...249Q.573Z Altcode: No abstract at ADS Title: Radio Carbon Evidence of the Global Stochasticity of Solar Activity Authors: Gizzatullina, S. M.; Rukavishnikov, V. D.; Ruzmaikin, A. A.; Tavastsherna, K. S. Bibcode: 1990SoPh..127..281G Altcode: An estimate of the dimension of the attractor of the dynamic system responsible for solar activity is obtained from the time series of carbon 14 experimental data (4300 BC to 1950 AD). According to this estimate the attractor is a fractal, in shape close to a 3-torus. The attractor's trajectories characterizing the evolution of the magnetic field exhibit irregular long-term behaviour. Title: On Forecasting the Sunspot Numbers Authors: Kurths, J.; Ruzmaikin, A. A. Bibcode: 1990SoPh..126..407K Altcode: We have applied a technique recently proposed basing on learning nonlinear dynamics locally to describe the annual sunspot relative numbers. It is proved that the number of past points for prediction should be greater than 4 but less than 10. This rather simple approach yields in average relatively good results for short-term forecasts (< 11 yr). Particularly, it predicts that the current cycle no. 22 will reach a very high maximum. However, this approach must be modified in the vicinity of a grand minimum. Title: Magnetic field in the Andromeda nebula inferred from polarization observations. Authors: Ruzmaikin, A.; Sokolov, D.; Shukurov, A.; Beck, R. Bibcode: 1990A&A...230..284R Altcode: We propose a method of pattern recognition intended primarily to determine the configuration of large-scale magnetic fields in external galaxies. Single-frequency polarization observations of M31 are analyzed, to determine parameters of the large-scale magnetic field in this galaxy. In the inner part of the magnetic ring in M31, for 7 < r < 10 kpc, deviations of the magnetic field configuration from axial symmetry are noticeable at the 95% confidence level. The basic axisymmetric component of the field can be distorted either by the north-south asymmetry of the disk of M31, revealed earlier in distributions of other constituents of the interstellar medium, or by the spiral pattern; other possible explanations of apparent deviations from axial symmetry are also proposed. In the outer parts of M31 a purely axisymmetric field distribution is consistent with the available observational data. Title: Book-Review - Magnetic Fields of Galaxies Authors: Ruzmaikin, A. A.; Shukurov, A. M.; Sokoloff, D. D.; Ward-Thompson, D. Bibcode: 1990JBAA..100...42R Altcode: No abstract at ADS Title: The flow in the Earth's interior caused by the mutual rotation of the mantle and the solid core. Authors: Nikitina, L. V.; Ruzmaikin, A. A. Bibcode: 1990Ge&Ae..30..127N Altcode: Differences in the angular velocities of the mantle and the solid core are found to lead to large-scale flow including differential rotation and meridional circulation in the density-stratified liquid outer core. The steady-state differential of angular velocities is sustained by the balance of moments of external (tidal) forces and internal viscous and magnetic friction. Title: Order and Chaos in the Solar Cycle Authors: Ruzmaikin, A. A. Bibcode: 1990IAUS..138..343R Altcode: No abstract at ADS Title: Large-Scale Internal Magnetic Field of the Sun Authors: Dudorov, A. E.; Krivodubskij, V. N.; Ruzmaikin, A. A.; Ruzmaikina, T. V. Bibcode: 1990IAUS..138..391D Altcode: No abstract at ADS Title: The almighty chance Authors: Zeldovich, Ya. B.; Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1990alch.book.....Z Altcode: No abstract at ADS Title: Intermittent Magnetic Fields Generated by Turbulence in Galaxies and Galaxy Clusters Authors: Sokolov, D. D.; Ruzmaikin, A. A.; Shukurov, A. Bibcode: 1990IAUS..140..499S Altcode: The turbulence of intracluster gas in galaxy clusters and interstellar gas in galaxies can act as a dynamo generating chaotic magnetic fields. These fields are concentrated in ropes. The field strength within the ropes is close to equipartition with turbulent kinetic energy. These results favorably agree with high-resolution observations of the galaxy cluster around Cyg A and correlation analysis of the Galactic nonthermal background. Ropy magnetic fields in interstellar gas lead to observable variations of, e.g., the Faraday depth at time scale of 1 month. Title: Dynamo in Astrophysics Authors: Ruzmaikin, A. A. Bibcode: 1990IAUS..140...83R Altcode: The origin of magnetic fields in astrophysical objects is developed theoretically in a discussion of the fast dynamo. Magnetic fields are described as being 'frozen,' but the complexity of turbulent astrophysical flows facilitates the generation of the magnetic field. The role of the mean magnetic field is considered in terms of stellar activity cycles as well as large-scale magnetic structures in spiral galaxies. Specific examples are given for the application of the notion of 'small-scale', intermittent magnetic fields to clusters of galaxies. The geometry of the Galactic dynamo is developed in terms of its mean helicity, as derived from observations of the velocity field. Plasma hydrodynamical motions are shown to preside in the inception of magnetic fields in stars and galaxies, and the dynamo process is theorized to be acting on observed plasmas with high magnetic Reynolds numbers. Title: Magnetic Intermittency Authors: Molchanov, S. A.; Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1990nowa.conf....2M Altcode: No abstract at ADS Title: Galactic Dynamo Theory Confronted with Observations Authors: Krasheninnikova, Iu. S.; Sokolov, D. D.; Ruzmaikin, A. A.; Shukurov, A. Bibcode: 1990IAUS..140..119K Altcode: Imprints of kinematic dynamo modes in observations of magnetic structures are evaluated in terms of theoretical models of galactic dynamos in axisymmetric disks. Direct comparisons of the theoretical implications of kinematic modes and observations of spiral galaxies are effective, but nonlinear effects evident in dynamos are not included in the description. Galactic dynamo theory can only be compared to observations in the Milky Way, where the asymptotic model is confirmed. The properties of linear dynamo models in the global magnetic configurations of spiral galaxies are examined, and nonlinear distortions of the linear solutions are identified. It is unclear whether the large-scale magnetic fields in the solar vicinity of the Milky Way have reached the steady state or whether the calculated value is accurate. Nonlinear effects in galactic dynamos are theorized to be relatively weak. Title: Maximally-efficient-generation approach in the dynamo theory Authors: Ruzmaikin, Alexander; Shukurov, Anvar; Sokoloff, Dmitry; Starchenko, Sergey Bibcode: 1990GApFD..52..125R Altcode: We propose a method of derivation of global asymptotic solutions of the hydromagnetic dynamo problem at large magnetic Reynolds number. The procedure reduces to matching the local asymptotic forms for the magnetic field generated near individual extrema of generation strength. The basis of the proposed method, named here the Maximally-Efficient-Generation Approach (MEGA), is the assertion that properties of global asymptotic solutions of the kinematic dynamo are determined by the distribution of the generation strength near its leading extrema and by the number and distribution of the extrema. The general method is illustrated by the global asymptotic solution of the 2-dynamo problem in a slab. The nature of oscillatory solutions revealed earlier in numerical simulations and the reasons for the dominance of even magnetic modes in slab geometry are clarified. Applicability of the asymptotic solutions at moderate values of the asymptotic parameter is also discussed. We confirm this applicability using comparisons with complementary asymptotic expansions and numerical simulations. In particular, this justifies application of the MEGA solutions to estimation of the generation threshold. Title: Generation of Cosmic Magnetic Fields Authors: Ruzmaikin, A. A. Bibcode: 1990ASIC..305..235R Altcode: 1990pphc.conf..235R The generation of magnetic fields by dynamo action of cosmic turbulent plasmas is considered. Three levels of the mechanism are discussed: (1) the mean field behaviour; (2) deviations from the mean field, i.e. magnetic fluctuations; and (3) the generation and distribution of random magnetic field in the random flow of a conducting plasma. Examples of magnetic fields generated in the interiors of Uranus and Neptune, in the Sun, and in clusters of galaxies are presented. Title: Dimension of geomagnetic attractor from data on length of day variations Authors: Malinetskii, G. G.; Potapov, A. B.; Gizzatulina, S. M.; Ruzmaikin, A. A.; Rukavishnikov, V. D. Bibcode: 1990PEPI...59..170M Altcode: Six-months averaged data on day length variations for 1656-1984 are used to obtain a lower bound of the dimension of the attractor of a dynamic system with the Earth's angular velocity as a variable. The noise level is estimated from the observations available. It is suggested that the data can be explained by using models with a few degrees of freedom. Some problems associated with the analysis of small data samples to determine the attractor dimension are discussed. Title: The galactic dynamo: Axisymmetric and non-axisymmetric modes Authors: Krasheninnikova, Yulia; Ruzmaikin, Alexander; Sokoloff, Dmitry; Shukurov, Anvar Bibcode: 1990GApFD..50..131K Altcode: We discuss recent developments in the theory of large-scale magnetic structures in spiral galaxies. In addition to a review of galactic dynamo models developed for axisymmetric disks of variable thickness, we consider the possibility of dominance of non-axisymmetric magnetic modes in disks with weak deviations from axial symmetry. Difficulties of straightforward numerical simulation of galactic dynamos are discussed and asymptotic solutions of the dynamo equations relevant for galactic conditions are considered. Theoretical results are compared with observational data. Title: Book-Review - Magnetic Fields of Galaxies Authors: Ruzmaikin, A. A.; Shukurov, A. M.; Sokoloff, D. D. Bibcode: 1989JBAA...99..313R Altcode: No abstract at ADS Title: On the origin of secular variations of the Earth's main magnetic field. Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Shukurov, A. M. Bibcode: 1989Ge&Ae..29.1001R Altcode: A mechanism is proposed for the excitation of magnetic disturbances that induce secular geomagnetic variations with characteristic times of less than 100 years (e.g., 60-year variations). These disturbances have the form of concentrated flux ropes and loops generated by the fluctuation-type MHD dynamo in the earth's liquid core. The observed variations are caused by ropes situated in the 60-km-thick skin layer near the core-mantle boundary. Title: The dynamo origin of magnetic fields in galaxy clusters. Authors: Ruzmaikin, Alexander; Sokolov, Dmitrii; Shukurov, Anvar Bibcode: 1989MNRAS.241....1R Altcode: The authors consider the gneration of magnetic fields by turbulent motions of intracluster gas in rich galaxy clusters. A qualitative discussion of the properties of intracluster MHD turbulence, its spectrum, characteristic scales and velocities, and estimation of hydrodynamic and magnetic Reynolds numbers is presented. Turbulence arises in the wakes of galaxies which move transonically through the gas. Magnetic field is generated at scales below the energy-range scale of turbulence. The magnetic fields are concentrated within thin intense ropes which occupy a small fraction of the total volume. The field strength within the ropes is about 10 μG, as determined by equipartition with kinetic energy of turbulence, while the rms field strength within a turbulent cell is as low as 2 μG. The correlation function of the chaotic magnetic field has a number of characteristic scales ranging from 20 kpc (the turbulence correlation scale) to 2×10-3kpc (the skin-layer thickness). The results are in agreement with observations of magnetic fields in the radiohaloes of galaxy clusters, in particular with recent observations of Cygnus A. Title: The large-scale internal solar magnetic field Authors: Dudorov, A. E.; Krivodubskij, V. N.; Ruzmaikina, T. V.; Ruzmaikin, A. A. Bibcode: 1989AZh....66..809D Altcode: It is hypothesized that, during the collapse of the protosolar cloud, the magnetic field intensified. In the center of the just-formed, nonturbulent sun, the intensity of the magnetic field was 10,000 to 1 million G. If the sun passed through a stage of turbulent convection, only the field generated by dynamo action would remain. The poloidal magnetic field at this stage could reach 1000-1,000,000 G, but the intensity would decrease to 10-1 G during the decay of turbulent convection. The toroidal magnetic field would remain at 1000-1,000,000 G. It is possible that nonuniform rotation of the radiative region is related to distortions in the angular velocity in the internal convective zone due to magnetic tension. Title: The Internal Largescale Magnetic Field of the Sun Authors: Dudorov, A. E.; Krivodubskii, V. N.; Ruzmaikina, T. V.; Ruzmaikin, A. A. Bibcode: 1989SvA....33..420D Altcode: No abstract at ADS Title: Negative Magnetic Pressure as a Trigger of Largescale Magnetic Instability in the Solar Convective Zone Authors: Kliorin, N. I.; Rogachevskii, I. V.; Ruzmaikin, A. A. Bibcode: 1989SvAL...15..274K Altcode: No abstract at ADS Title: The effect of negative magnetic pressure and the large-scale magnetic field instability in the solar convective zone Authors: Kleeorin, N. I.; Rogachevskii, I. V.; Ruzmaikin, A. A. Bibcode: 1989PAZh...15..639K Altcode: No abstract at ADS Title: Configuration of large-scale magnetic fields in spiral galaxies. Authors: Krasheninnikova, Iu.; Shukurov, A.; Ruzmaikin, A.; Sokolov, D. Bibcode: 1989A&A...213...19K Altcode: Within the framework of the thin-disc galactic dynamo model of Baryshnikova et al. (1987), magnetic lines for the axisymmetric m = 0 and non-axisymmetric m = 1 dynamo modes are presented. The calculated pitch angles of magnetic lines in the galaxies M31, M51, M81, IC 342 and the Milky Way agree with observational data. Spatial distributions of the Faraday rotation measures produced by axisymmetric and non-axisymmetric fields and their superpositions are discussed. Effective generation of the m = 1 dynamo mode in M81 is shown. Distribution of magnetic field in IC 342 is discussed in detail. It is shown that measurements of pitch angles of magnetic lines in outer parts of galaxies can be used for estimation of the ratio of the energy-range scale of interstellar turbulence to the thickness of the ionized gaseous disc. We discuss possible reasons of presence of bisymmetric fields among the observed magnetic structures. Non-axisymmetric distortions of the galactic disc with azimuthal wave number one result in two effects first, the basic dynamo mode, remaining axisymmetric at small galactocentric distances, acquires a m = 1 correction in the outer part of the disc. Second, the difference between the growth rates of the m = 0 and m = 1 dynamo modes considerably decreases In contrast, weak perturbations from spiral arms do not affect growth rates of bisymetric dynamo modes Additional generation of the azimuthal field by helical turbulence (α^2^-dynamo) cannot make non-axisymmetric modes prevalent in a thin disc. Title: Generation of large-scale magnetic fields on Uranus and Neptune by turbulent dynamo mechanism. Authors: Ruzmaikin, A. A.; Starchenko, S. V. Bibcode: 1989KosIs..27..292R Altcode: 1989CosRe..27..292R It is shown that the observed magnetic field of Uranus is a vector sum of fields generated by the turbulent dynamo in the core of the planet and the thin conducting shell surrounding the core. The large inclination of the dipole moment to the axis of rotation is connected with the predominant excitation of an axisymmetric field in the core, and the predominant excitation of a nonaxisymmetric field in the conducting shell. A configuration with a small inclination of the dipole to the axis of rotation is expected for Neptune. Title: A generalized two-disk dynamo model Authors: Ershov, Sergey V.; Malinetskii, George G.; Ruzmaikin, Alexander A. Bibcode: 1989GApFD..47..251E Altcode: A generalized two-disk dynamo model is considered that includes mechanical friction; this model is intended to simulate in its broad character the behavior of the geodynamo. Fixed points, limit cycles and chaotic attractors are located for different input parameters of the model. The chaotic regimes are of several kinds as are the "routes to chaos". Several approximate models, helpful for studying the dynamo are discussed. A number of essential differences from the well-known Rikitake dynamo are demonstrated. Title: Correlation function and spectrum of solar small-scale magnetic fields. Authors: Kliorin, N. I.; Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1988KFNT....4...28K Altcode: Spectrum and time correlation function of a magnetic field generated by reflectionally invariant short-correlated turbulent flow are found. The results can be applied to study the correlation features of a solar small-scale magnetic field independent of the solar cycle. Title: Magnetohydrodynamic effect of differential rotation in a conducting spherical region Authors: Brodskii, Iu. A.; Krasheninnikova, Iu. S.; Ruzmaikin, A. A. Bibcode: 1988MagGi.......13B Altcode: A solution is presented for the problem of the eigenvalues and eigenfunctions of a magnetic field decreasing at infinity for a spherically symmetric rotating conducting region. Under conditions of continuously distributed differential rotation, a nonaxisymmetric magnetic field is completely displaced from the rotating region in the limit of strong rotation. However, when changes in the angular rotation velocity are concentrated near a certain radius, the eigenfunctions are divided into two groups: internal (localized inside the rotating region) and external. Thus, under conditions of concentrated differential rotation, there is always a magnetic field in the rotating region. The magnetic basis proposed here is important for stellar and planetary dynamo models. Title: The mean-field kinematic turbulent geodynamo Authors: Ruzmaikin, A. A.; Starchenko, S. V. Bibcode: 1988Ge&Ae..28..475R Altcode: A WKB asymptotic method is used to obtain a solution to the kinematic problem concerning the generation of the large-scale geomagnetic field. The turbulent-dynamo generation of the mean field due to differential rotation and helicity is considered. The solution obtained yields a natural explanation for the small inclination of the dipole component of the geomagnetic field and the westward drift of magnetic irregularities (the first nonaxisymmetric field modes). Title: Magnetic Field in the Perseus Arm Authors: Agafonov, G. I.; Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1988SvA....32..268A Altcode: No abstract at ADS Title: Excitation of Non-Axially Symmetric Modes of the Sun's Mean Magnetic Field Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Starchenko, S. V. Bibcode: 1988SoPh..115....5R Altcode: The kinematic dynamo equations for the mean magnetic field are solved with an asymptotic method of the WKB type. The excitation conditions and main characteristics of the non-axially symmetric modes for a given distribution of the sources are obtained. Utilization of the helioseismologic data on the Sun's internal rotation permits an explanation, within the framework of dynamo theory, of the excitation of the main non-axially symmetric modes revealed in the Sun's magnetic field sector structure. Title: Magnetic field origin in astrophysical jets Authors: Gvaramadze, V. V.; Lominadze, Dzh. G.; Ruzmaikin, A. A.; Sokolov, D. D.; Shukurov, A. M. Bibcode: 1988AdSpR...8b.621G Altcode: 1988AdSpR...8..621G We propose and analyze a possible mechanism of amplification and variations in alignment of magnetic fields in astrophysical jets. We associate these processes with combined action of helical turbulent plasma motions and large-scale velocity within a jet which stretch and distort a seed magnetic field. Title: Turbulent Generation of Magnetic Fields in Astrophysical Jets Authors: Gvaramadze, V. V.; Lominadze, J. G.; Ruzmaikin, A. A.; Sokoloff, D. D.; Shukurov, A. M. Bibcode: 1988Ap&SS.140..165G Altcode: We consider evolution of the regular magnetic field in turbulent astrophysical jets. The observed lateral expansion of a jet is approximately described by a linear in coordinates regular velocity field (the Hubble flow). It is shown that in expanding turbulent jets with non-vanishing mean helicity of the turbulence temporal amplification and effective realignment of the regular magnetic field occurs with the field changing orientation from the transverse to the longitudinal one along the jet axis. The distance at which the realiggment occurs depends on parameters of the jet, in particular, on the power of the central source. Estimates for the jet in a weak source 3C 31 favourably agree with observations. Title: On the cyclicity and amplitude of the activity of rotating stars Authors: Kleeorin, N. I.; Ruzmaikin, A. A. Bibcode: 1988mast.conf..321K Altcode: No abstract at ADS Title: Magnetic Manifestations of Solar Rotation Authors: Ruzmaikin, A. A.; Starchenko, S. V. Bibcode: 1987SvA....31..552R Altcode: No abstract at ADS Title: Magnetic waves of solar activity. Authors: Makarov, V. I.; Ruzmaikin, A. A.; Ruzmajkin, A. A.; Starchenko, S. V. Bibcode: 1987SoPh..111..267M Altcode: An asymptotic solution of generation equations for the solar mean magnetic field is given and studied. The variation of rotational angular velocity with depth is taken from helioseismological data. Average helicity is prescribed according to the mixing length theory. It is shown that three dynamo waves of the magnetic field are excited. The first wave is generated at the surface layer and concentrates at latitudes of about 60°. Its activity becomes apparent in the poleward migration of the zone of polar faculae formation. The second more powerful wave of the field is excited in the center of the convection zone and its activity shows up in a sunspot cycle. The third wave which is similar to the first wave, is generated at the bottom of the convection zone and attenuates towards the surface. Its activity may appear as a three-fold reversal of the polar magnetic field. Title: Generation of large-scale magnetic fields in spiral galaxies. Authors: Baryshnikova, Iu.; Shukurov, A.; Ruzmaikin, A.; Sokoloff, D. D. Bibcode: 1987A&A...177...27B Altcode: The authors discuss the origin of bisymmetric and ring-like large-scale magnetic structures in spiral galaxies. They develop further the idea that bisymmetric structures observed in several galaxies are the result of the generation of non-axisymmetric large-scale magnetic fields by the turbulent dynamo mechanism. Observations indicate the ring-like magnetic structure in M31 and the bisymmetric one in M51. The situation in the Milky Way is more complicated. Our galaxy's rotation is such that a non-axisymmetric magnetic field can only be generated here if the half-thickness of the ionized gaseous disc in the solar vicinity lies between 540 and 720 pc. Otherwise only axisymmetric fields are generated. Unfortunately, observations allow a much wider range of possible disc half-thicknesses, ranging from 400 to 1000 pc. The authors propose some observational tests for verification of their theory. Title: Self-oscillations of a disk dynamo Authors: Kliorin, N. I.; Lominadze, Dzh. G.; Ruzmaikin, A. A.; Chagelishvili, G. D. Bibcode: 1987MagGi........3K Altcode: The problem of a turbulent dynamo in a thin disk with a simple nonlinearity is examined analytically. It is shown that a nonlinear system is characterized by self-oscillations, whereas a linear solution involves monotonic field growth. If differential rotation is sufficiently large, the magnetic field amplitude may exceed the equal distribution level, which may be an important factor in explaining the observed spectra of accretion disks. Title: Magnetic fields of galaxies. Authors: Ruzmaikin, A.; Ruzmajkin, A. A. Bibcode: 1987imfo.work...16R Altcode: A global structure of the mean magnetic field in spiral galaxies is presented. The discovery of two-spiral or bisymmetric configurations in M51, M81, M33, NGC 6946 is reported. It is noted that the bisymmetric magnetic structure can be interpreted as the lowest nonaxisymmetric mode excited by the dynamo action. The structure of the maximal magnetic field intensity for a galaxy like M51 is indicated schematically. Title: Magnetic fields of spiral galaxies Authors: Ruzmaikin, A. A.; Sokoloff, D. D.; Shukurov, A. M. Bibcode: 1986ESASP.251..539R Altcode: 1986plas.work..539R Observational data and theoretical results on the large-scale magnetic fields in spiral galaxies are reviewed. Observed variations of position angle of polarized radio emission over a galaxy image are discussed. Observational data for our Galaxy are insufficient to decide whether the galactic magnetic field has circular or bisymmetric structure. Estimates and numerical calculations show that bisymmetric magnetic structures observed in many galaxies are the result of excitation of the lowest non axisymmetric magnetic field mode by the turbulent dynamo. The growth time for bisymmetric field in M51 is 300 million yr. In contrast, all non axisymmetric modes decay in M31, in accordance with observations. A source of galactic seed field due to superposition of magnetic loops ejected by supernovae is proposed. Title: Correlative properties of self-exciting fluctuative magnetic fields Authors: Kleeorin, N. I.; Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1986ESASP.251..557K Altcode: 1986plas.work..557K Correlation function of the magnetic fields excited in a reflectionally symmetrical shortcorrelated turbulent flow is constructed. It is based on an asymptotical solution valid at large magnetic Reynolds numbers Rm. Two magnetic correlation scales appear: l×Rm-1/2 and l×Rm-1/4 in addition to l, where l is a basic scale of the turbulence. The results are discussed in application to the Sun and Galaxy. Title: Book-Review - Magnetic Fields in Astrophysics Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D.; Kleczek, J. Bibcode: 1986Ap&SS.120..155Z Altcode: No abstract at ADS Title: - / Partial Distribution of the Mean Total Magnetic Flux of Sunspots Authors: Ruzmaikin, A. A.; Tavastsherna, K. S. Bibcode: 1986BSolD..10...78R Altcode: No abstract at ADS Title: Book-Review - Magnetic Fields in Astrophysics Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D.; Downes, A. Bibcode: 1985Obs...105..213Z Altcode: No abstract at ADS Title: The Solar Dynamo Authors: Ruzmaikin, A. A. Bibcode: 1985SoPh..100..125R Altcode: The basic features of the solar activity mechanism are explained in terms of the dynamo theory of mean magnetic fields. The field generation sources are the differential rotation and the mean helicity of turbulent motions in the convective zone. A nonlinear effect of the magnetic field upon the mean helicity results in stabilizing the amplitude of the 22-year oscillations and forming a basic limiting cycle. When two magnetic modes (with dipole and quadrupole symmetry) are excited nonlinear beats appear, which may be related to the secular cycle modulation. Title: Anisotropy of Turbulent Transport in a Convective Layer Authors: Monin, A. S.; Rakhmanova, N. K.; Ruzmaikin, A. A. Bibcode: 1985Ap&SS.114..157M Altcode: An estimate for the anisotropy of the turbulent viscositys is given in a convective layer heated from below and rotating around a vertical axis. In the case of two-dimensional convection, there is a stationary regime withs⊇2 regardless of the rotation. In the case of three-dimensional convection in a slowly rotating layer (with the Taylor number equal to 1600), nonstationary turbulent regimes take place withs⊇1.6 forR=2.5×104 (R is the Rayleigh number) ands⊇1.2 forR=104. The parameters plays an, important role in the theory of differential rotation of the convective solar or stellar envelopes. So far, it has been evaluated empirically or semi-empirically. Some prospects in the development of the theory of differential rotation are discussed here in terms of the moment theory of hydrodynamic fields. The relation between this strict approach and an anisotropic viscosity approximation is considered. Title: Book-Review - Magnetic Fields in Astrophysics Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D.; van der Hucht, K. A. Bibcode: 1985SSRv...41..400Z Altcode: No abstract at ADS Title: Book-Review - Magnetic Fields in Astrophysics Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D.; Martens, P. C. H. Bibcode: 1985SoPh...98..195Z Altcode: No abstract at ADS Title: Magnetic field distribution in spiral galaxies. Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Shukurov, A. M. Bibcode: 1985A&A...148..335R Altcode: The spatial distribution of large-scale magnetic fields in gaseous discs of spiral galaxies is discussed. The authors propose an asymptotic method of solution of the kinematic turbulent dynamo equations that is based on the smallness of the ratio of the disc thickness to its radius. All generated modes of the large-scale magnetic field have similar distributions over the vertical coordinate. However, a great number of modes with different radial behavior are excited simultaneously. A special attention is paid to comparison of these results with observations of the magnetic fields of spiral galaxies, e.g. the Galaxy, M31, IC 342, M81. Title: Book-Review - Magnetic Fields in Astrophysics Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D.; Mestel, L. Bibcode: 1985Natur.313..606Z Altcode: No abstract at ADS Title: Three-dimensional model for generation of the mean solar magnetic field Authors: Ivanova, T. S.; Ruzmaikin, A. A. Bibcode: 1985AN....306..177I Altcode: A three-dimensional (non-axisymmetric) model for the solar mean magnetic field generation is studied. The sources of generation are the differential rotation and mean helicity in the convective shell. The system is described by two equations of the first order in time and the fourth order in space coordinates. The solution is sought for in the form of expansion over the spherical functions Y(m)n. The modes of different m are separated. A finite-difference scheme similar to the Peaceman-Rachford scheme is constructed in order to find coefficients of the expansion depending on the time and radial coordinates. It is shown that a mode with a smaller azimuthal number m is primarily excited. The axisymmetric mode m = o describes the 22 year solar cycle oscillations. The modes of m o have no such periodicity, they oscillate with a period of rotation of the low boundary of the solar convective shell. The solutions which are symmetric relative to the equator plane are excited more easily compared with the antisymmetrical ones. The results obtained are confronted to the observational picture of the non-axisymmetric large-scale solar magnetic fields. Title: Book-Review - Magnetic Fields in Astrophysics Authors: Zeldovich, Y. B.; Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1984JBAA...95...46Z Altcode: No abstract at ADS Title: The nature of the 11-year solar torsional oscillations Authors: Kliorin, N. I.; Ruzmaikin, A. A. Bibcode: 1984PAZh...10..925K Altcode: The 22-yr dynamo wave in the global solar magnetic field does indeed generate the observed 11-yr torsional oscillations. The drift direction, amplitude, and phase shift of the torsional wave relative to the magnetic activity all agree with LaBonte and Howard's (1982) measurements. Superposition of the dipole and quadrupole symmetry modes produces secular asymmetry in the differential rotation relative to the solar equator. Title: Non-linear dynamos. Authors: Ruzmaikin, A. A. Bibcode: 1984ESASP.220...85R Altcode: 1984ESPM....4...85R The basic large-scale features of solar activity are explained by dynamo theory in terms of mean-field magnetohydrodynamics. The helicity dependence on the magnetic field results in stabilization of the basic 22-year oscillations. The excitation of two modes (of dipole and quadrupole symmetry) can create non-linear beats which may explain the secular (60 - 80 years) modulation. The observed torsional waves can be interpreted as a back action of the dynamo waves on the differential rotation. The actual variations in solar activity are non-periodic. There are random recurrent episodes of reduced activity like the Maunder Minimum. The non-linear dynamo models demonstrating the oscillatory-chaotic behaviour are discussed. Title: A dynamo theorem Authors: Molchanov, S. A.; Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1984GApFD..30..241M Altcode: It is shown that the frozen-in magnetic field in a given random homogeneous flow of an incompressible fluid which is renewed after a finite characteristic time grows exponentially. The rate-of-growth is positive in the limit of small magnetic diffusivity and continuous in the frozen-in condition Vm. The increase of the rates-of-growth for successive field moments is revealed by the intermittent distribution of the magnetic field generated. The results are obtained by reducing the kinematic dynamo problem to the evaluation of the product of a large number of independent random operators. Title: Magnetic field generation in an anisotropically conducting fluid Authors: Ruderman, M. S.; Ruzmaikin, A. A. Bibcode: 1984GApFD..28...77R Altcode: An example of an exponentially growing magnetic field in a fluid with shear and a homogeneous but anisotropic magnetic diffusivity is constructed. An induction equation for an anisotropic fluid is derived and a solution of the dynamo type in an unbounded fluid is obtained. The motion with one coordinate bounded is analyzed. A similarity between the solutions and the known homopolar disk dynamo is noted. Title: Mean maganetic field in renovating random flow Authors: Dittrich, P.; Molchanov, S. A.; Sokolov, D. D.; Ruzmaikin, A. A. Bibcode: 1984AN....305..119D Altcode: An integral equation is derived for a mean magnetic field in a random velocity field that renovates after a characteristic time τ. It is shown that in two cases, i.e. when (1) the correlation time is short, τ very low l/v0 (where l and v0 are the characteristic scale and velocity), and (2) for long wave components of the field, k-1 very large v0τ, the equation is reduced to the differential one, whose form has first been given by Steenbeck, Krause and Rädler. Expressions for the equation coefficients are obtained in the two above cases. In a general case the integral equation cannot be reduced to the differential one although its spectral properties are close in a certain sense to those of the SKR-equation. There are differences, however, that are shown on the example of the Gaussian distribution of particles moving along random paths. Title: Kinematic dynamo problem in a linear velocity field Authors: Zel'dovich, Ya. B.; Ruzmaikin, A. A.; Molchanov, S. A.; Sokolov, D. D. Bibcode: 1984JFM...144....1Z Altcode: No abstract at ADS Title: Turbulent dynamo Authors: Ruzmaikin, A. A. Bibcode: 1984ntpp.proc..481R Altcode: A solution of the kinematic dynamo problem for a random renovating flow modulating a turbulence is presented. A general solution of the Cauchy problem is first obtained for the exponentially growing solution of the magnetic field of an incomressible fluid with a constant magnetic diffusivity. The solution is then used to derive moment equations for the magnetic field for the case of a short-time correlated velocity field. Finally, the dynamo theorem is presented, which describes the magnetic field behavior at R(m) (magnetic Reynolds number) approaching infinity. It is concluded that the field distribution is nonhomogeneous in space. Title: Mean Magnetic Field in Renovating Random Flow Authors: Dittrich, P.; Molchanov, S. A.; Sokoloff, D. D.; Ruzmaikin, A. A. Bibcode: 1984AN....305Q.119D Altcode: No abstract at ADS Title: Gemittelte magnetische Felder in sich erneuernden Zufallsströmungen Authors: Dittrich, P.; Molchanov, S. A.; Sokoloff, D. D.; Ruzmaikin, A. A. Bibcode: 1984AN....305R.119D Altcode: No abstract at ADS Title: Mean-field dynamo with cubic non-linearity Authors: Kleeorin, N. I.; Ruzmaikin, A. A. Bibcode: 1984AN....305..265K Altcode: A turbulent mean-field alpha-omega dynamo model of magnetic-field generation in astrophysical objects is developed, assuming a quadratic dependence of the helicity on the magnetic field. The mean-field equation for cubic nonlinearity is reduced to a system of infinite equations with coefficients determined by the eigenfunctions and eigenvalues of the linear problem, and the one-mode and two-mode approximations are examined in detail. The supercritical solution in the one-mode approximation is found to be stable for d(gamma)/dD greater than zero, where gamma is the growth rate of the linear solution and D is the dynamo number. In the two-mode approximation, the nonlinear interaction of a dipole mode and a weaker quadrupole mode is used to derive the conditions for synchronization and beating. Title: The nature of the 11-year solar torsional oscillations Authors: Kliorin, N. I.; Ruzmaikin, A. A. Bibcode: 1984SvAL...10..390K Altcode: No abstract at ADS Title: Mean-Field Dynamo with Cubic Non-Linearity Authors: Kleeorin, N. I.; Ruzmaikin, A. A. Bibcode: 1984AN....305R.265K Altcode: No abstract at ADS Title: Mean-Field Dynamo mit kubischer Nichtlinearität Authors: Kleeorin, N. I.; Ruzmaikin, A. A. Bibcode: 1984AN....305Q.265K Altcode: No abstract at ADS Title: Asymptotic solution of the mean field dynamo problem Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Shukurov, A. M. Bibcode: 1984ntpp.proc..489R Altcode: An asymptotic solution is found for the turbulent dynamo equation to describe the evolution of the magnetic field of an astronomical object. The solution to the problem is based on a quasi-classical approximation from quantum mechanics. The cases of helical turbulence and large-scale velocity shear are treated independently. It is found that the asymptotic solution permits estimates of such parameters as the growth rate of the mean magnetic field, its configuration, and the threshold for generation of the magnetic field. Title: A Dynamo Theorem Authors: Molchanov, S. A.; Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1984GApFD..30..242M Altcode: No abstract at ADS Title: Activity Cycle Periods in Late-Type Stars Authors: Kleeorin, N. I.; Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1983Ap&SS..95..131K Altcode: Period of magnetic activity versus the stellar angular velocity for stars of given spectral type having extended convective shells is estimated within the framework of mean field dynamo theory. The dependence appears to be not monotonous, and can be checked by observations. Title: Asymptotic solution of the alpha-squared-dynamo problem Authors: Sokolov, D.; Shukurov, A.; Ruzmaikin, A. Bibcode: 1983GApFD..25..293S Altcode: The turbulent dynamo equation with non-uniform mean helicity is solved in an approximation, which is similar to the quasi-classical approximation of quantum mechanics. The rate of growth of the magnetic field is evaluated and a condition for dynamo action is obtained. The generated magnetic field is concentrated in the vicinity of an extremum of mean helicity but in general vanishes at the point of the extremum. The field is asymptotically force-free. The results obtained here clarify the fact, known from numerical calculations, that the threshold values of the dynamo-number for excitation of dipole and quadrupole modes are very close to each other. Title: Non-linear problems of the solar dynamo Authors: Ruzmaikin, A. A. Bibcode: 1983spm..conf..151R Altcode: No abstract at ADS Title: Magnetic fields in astrophysics Authors: Zeldovich, Ia. B.; Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1983flma....3.....Z Altcode: The evidence of cosmic magnetism is examined, taking into account the Zeeman effect, beats in atomic transitions, the Hanle effect, Faraday rotation, gyro-lines, and the strength and scale of magnetic fields in astrophysics. The origin of magnetic fields is considered along with dynamos, the conditions for magnetic field generation, the topology of flows, magnetic fields in stationary flows, kinematic turbulent dynamos, the turbulent dynamo in a disk, topics in nonlinear turbulent dynamo theory, stellar cycles, the galaxy and its magnetic field, the galactic dynamo, the role of magnetic fields in star formation, magnetic fields in cosmology, accretion on black holes, and strong magnetic fields. Attention is given to frozen-in magnetic fields, a relict field hypothesis, the random walk of fluid particles, the problems of stellar taxonomy, evidence of stellar activity, the stochastic nature of the prolonged weakening of solar activity, the evolution of magnetic clouds, pulsars, and the problem of magnetic charges, referred to as 'monopoles'. Title: Dynamo problems in astrophysics Authors: Zeldovich, Ia. B.; Ruzmaikin, A. A. Bibcode: 1983ASPRv...2..333Z Altcode: Some current topics in hydromagnetic dynamo theory are discussed in the astrophysical context of large magnetic Reynolds number. Criteria are defined for field generation in a state of near-complete freezing-in. An account is given of certain qualitative aspects of a turbulent dynamo operating through nonuniform rotation of a conducting medium subject to random motions with helicity. Such dynamos might be at work in planetary cores, stellar envelopes, galaxies, and the gaseous accretion disks around X-ray sources. The concepts of stochasticity and strange attractors in a magnetic dynamo are examined, and a qualitative interpretation is offered for the occasional prolonged interruptions of the solar activity cycle, such as the Maunder minimum. Title: Spectrum of the Galactic Magnetic Fields Authors: Ruzmaikin, A. A.; Shukurov, A. M. Bibcode: 1982Ap&SS..82..397R Altcode: The magnetic fields observed in the galactic disc are generated by the differential rotation and the helical turbulent motions of interstellar gas. On the scalesl=2πk -1 which lie in the intervall 0<l<l e (l 0≃100 pc is the energy-range scale of the galactic turbulence), the spectral density of the kinetic energy of turbulence (∝k -5/3) exceeds the magnetic energy spectral density (∝k -1). The equipartition between magnetic and kinetic energies is reached atl=l e ≃6 pc in the intercloud medium and is maintained down to the scalel=l d ≃0.03 pc. In dense interstellar cloudsl e is determined by the individual cloud size andl d ≃0.1 pc.The internal turbulent velocities in H i clouds (cloud size is assumed to be 10 pc) lie in the range from 1.8 to 5.6km s-1, fitting well within the observed range of internal rms velocities. Dissipation of the interstellar MHD turbulence leads to creation of temperature fluctuations with amplitudes of 150 K and 65 K in dense clouds and intercloud medium, respectively. The small-scale fluctuations observed in the interstellar medium may arise from such perturbations due to the thermal instability, for instance. Dissipation of the MHD turbulence energy provides nearly half of the energy supply needed to maintain the thermal balance of the interstellar medium. Title: The magnetic field in mirror-invariant turbulence Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1981PAZh....7..701R Altcode: Exponential magnetic field growth in a mirror-symmetric (in the mean) turbulent conducting fluid is shown to be possible. The back action of the field on the turbulent motion is neglected. The excitation criterion and spectrum are obtained for small wave numbers. Title: Asymptotic Properties of Disk Dynamo Authors: Isakov, R. V.; Ruzmaikin, A. A.; Sokolov, D. D.; Faminskaia, M. V. Bibcode: 1981Ap&SS..80..145I Altcode: The asymptotic properties of a turbulent disk dynamo at large dimensionless numbersR α andR ω characterizing the helicity and the differential rotation are analysed. Three types of generations in the dependence of the relations betweenR α andR ω are found: α2-dynamo and two types of αω-dynamo. For each of these types the rates of growth are obtained and the forms of solution are pointed out. Boundaries of the disk dynamo approximation are given. Title: Magnetic Field Generation in the Galactic Disk Authors: Ruzmaikin, A. A.; Shukurov, A. M. Bibcode: 1981SvA....25..553R Altcode: No abstract at ADS Title: Magnetic field generation in the galactic disk Authors: Ruzmaikin, A. A.; Shukurov, A. M. Bibcode: 1981AZh....58..969R Altcode: A model is developed wherein large-scale magnetic field generation in the Galaxy is determined by two dimensionless dynamo numbers. This relationship is examined using the observed rotation curve of the Galaxy and taking into account the radial variations of the ionized gas layer thickness and of the characteristic velocity of turbulent motions. It is found that the (alpha)(omega) dynamo operates in the main body of the galactic disk, producing an even nonoscillatory azimuthal field and a quadrupole poloidal field. However, in the innermost part of the Galaxy, the alpha-squared dynamo may operate, and both oscillatory and steady fields of both dipole and quadrupole symmetry are possible. The spatial boundaries of the regions of dynamo action are estimated using the analytical solutions of thin-disk dynamo equations obtained in the concentrated helicity approximation. The present model may also be applied to other spiral galaxies, e.g., M31, M81, and NGC 4594. Title: The Magnetic Field in Mirror-Invariant Turbulence Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1981SvAL....7..388R Altcode: No abstract at ADS Title: The solar cycle as a strange attractor Authors: Ruzmaikin, A. A. Bibcode: 1981ComAp...9...85R Altcode: The observed 11-year (or 22-year) cycle is not harmonic; short-term disturbances and a long-term modulation are clearly noted. The most impressive fact is a sharp weakening of solar activity in the period 1645-1715 (Maunder's minimum) and possibly in earlier epochs. Nonlinear dynamo theory is necessary to explain these features of the solar cycle. Such a theory does not yet exist, but some fragments of a future theory are discussed in this paper in connection with observational phenomena. Attention is given to the mechanism of solar activity, 11-year activity, quasi-periodic modulation, and the stochastic nature of the prolonged weakening of solar activity. Title: Properties of a nonlinear solar dynamo model Authors: Kleeorin, N. I.; Ruzmaikin, A. A. Bibcode: 1981GApFD..17..281K Altcode: A simple nonlinear model is developed for the solar dynamo, in which the real convective spherical shell is approximated by a thin flat slab, and only the back-reaction of the field B on the helicity is taken into account by choosing the simple law = (1-B2), where and are constants, to represent the decrease in generation coefficient with increasing field strength. Analytic expressions are obtained for the amplitude of the field oscillation and its period, T, as functions of the deviation d - dCT of a dynamo number d from its critical value dcr for regeneration. A symmetry is found for the case of oscillations of small constant amplitude: B(t+½T)= -B(t). A Landau equation is obtained that describes the transition to such oscillations. Title: A disk dynamo with concentrated spirality Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Shukurov, A. M. Bibcode: 1980MagGi..16...20R Altcode: The paper determines exact solutions of the equations for a thin disk with a simultaneous consideration of alpha(omega) and alpha square effects with a helicity function of alpha of the delta-type. It is shown that such helicity can originate in a rotating turbulent disk with a density discontinuity. The solutions have a discontinuous character, and an associated specific nonlinear effect was also found. Title: The Turbulent Dynamo in a Disk Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Turchaninov, V. L. Bibcode: 1980SvA....24..182R Altcode: No abstract at ADS Title: The turbulent dynamo in a disk Authors: Ruzmaikin, A. A.; Sokoloff, D. D.; Turchaninoff, V. I. Bibcode: 1980AZh....57..311R Altcode: The large-scale magnetic field in a rotating, turbulent gaseous disk will be generated by a dynamo process (the alpha-omega-dynamo) determined by the differential rotation omega (r) and the spirality function alpha (z). The generation is best described by a difference approximation to the dynamo equations, using a step greater than the turbulence correlation length and a smooth function alpha (z). The critical dynamo-number for exciting the lowest even quadrupole mode is Dq = -8. The odd dipole mode will be excited only for large dynamo-numbers, /Dd/ equal to or greater than 500. When /D/ equal to or greater than 20, all modes other than the lowest quadrupole mode (for which the threshold D = -500) are oscillatory. The results are applied to the Galaxy (D = -10; characteristic growth time, 3 x 10 to the 8th yr) and to accretion disks in binary systems containing a black hole, where several oscillatory modes can be excited. Title: A disk dynamo with concentrated helicity Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Shukurov, A. M. Bibcode: 1980MagGi.......20R Altcode: The paper determines exact solutions of the equations for a thin disk with a simultaneous consideration of alpha(omega) and alpha square effects with a helicity function of alpha of the delta-type. It is shown that such helicity can originate in a rotating turbulent disk with a density discontinuity. The solutions have a discontinuous character, and an associated specific nonlinear effect was also found. Title: The Role of Differential Rotation in the Solar Dynamo Authors: Ivanova, T. S.; Ruzmaikin, A. A. Bibcode: 1980SvA....24...75I Altcode: No abstract at ADS Title: The role of differential rotation in the solar dynamo Authors: Ivanova, T. S.; Ruzmaikin, A. A. Bibcode: 1980AZh....57..127I Altcode: A nonlinear magnetohydrodynamic model of the solar dynamo is considered. It is shown that in order for the solar dynamo theory to be consistent with observations it is necessary that the angular velocity of the convective shell have a radial gradient and that this gradient be negative. Title: Helicity, linkage and dynamo action Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1980GApFD..16...73R Altcode: A flux helicity pseudoscalar that determines the number of linked flow lines in a simply connected volume is introduced along with a scalar that is proportional to the number of linkages of flow lines with magnetic field lines. These quantities are used to develop a topological formulation of an antidynamo theorem. The conditions required for slow dynamo action are clarified, and the relation between flux helicity and the usual vortex helicity is considered. Title: The turbulent dynamo in astrophysics Authors: Vainshtein, S. I.; Zeldovich, Ia. B.; Ruzmaikin, A. A. Bibcode: 1980MoIzN....R....V Altcode: The work examines fundamental aspects of the derivation of equations of generation and restructuring of magnetic fields in dynamo theory. The generation and restructuring processes are examined in the linear and nonlinear field approximations. As examples, consideration is given to the solar dynamo, the generation of the large-scale magnetic field of the Galaxy, and magnetic fields and vortex motions in cosmology. Title: The Disc Dynamo Authors: Ruzmaikin, A. A.; Turchaninov, V. I.; Zeldovich, Ia. B.; Sokoloff, D. D. Bibcode: 1979Ap&SS..66..369R Altcode: The simplest αω dynamo in a thin disk is analysed. It the antisymmetric helicity function α(z) (wherez is a coordinate perpendicular to the disk plane) is smooth and limited, then the conditions for generating a magnetic field and the symmetry of the resulting solutions depend only on the form of α at the segment (0,h) — whereh is the half-thickness of the disk — and the value of the dimensionless dynamo numberD. When α(z) does not change its sign at this segment andD>D c (the critical dynamo number), the excitation of non-oscillating even (quadrupole) and oscillating odd (dipole) fields are possible. When α(z) changes its sign at the segment indicated, non-oscillating odd magnetic fields can also be excited. The old exact solutions of the disk αω dynamo are studied and new ones are found. The results can be of importance when applied to the problem of the generation of a magnetic field in galactic and turbulent disks appearing around some X-ray sources. Title: The calculation of Faraday rotation measures of cosmic radio sources. Authors: Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1979A&A....78....1R Altcode: Summary. An observational procedure and a method to calculate rotation measures and the intrinsic position angles of polarization of cosmic radio sources is proposed. To avoid the difficulty introduced by the ambiguity of a position angle (* kx, k =0,1,2,...) it is necessary firstly to carry out the observations at two sufficiently close wavelengths and then to choose the next wavelength so that only one value of the position angle will fall into a cone of possible straight lines drawn through the previous wavelengths. The calculation procedure is realized with a computer. The method has been applied to a sample (of non specialized data) of observations available and the rotation measures and intrinsic position angles for 145 radio sources have been obtained, 35 of them are new and the rest coincide partially with those previously published. The main characteristic of the extragalactic radio sources in our catalogue is the nearly complete absence of very large rotation measures (>200 rad/m2). This is evidence against the hypothesis of an extragalactic radio source population with large rotation measures (Kronberg and SimardNormardin, 1976). Key words: rotation measure - position angle - polarisation data processing - extragalactic and galactic radio sources Title: Faraday rotation in galaxies and absorption lines of quasars. Authors: Komberg, B. V.; Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1979PAZh....5...73K Altcode: The proposal is made that the dispersion in rotation measure or the dispersion in depolarization be estimated for various samples of quasars (with and without absorption lines in their optical spectrum) with red shifts in the range 1.7-2.4. The difference in these dispersions for quasars with and without absorption lines would, in principle, yield the rotation measure for intervening galaxies along the line of sight that are responsible for the absorption lines. Title: A disk dynamo Authors: Zeldovich, Ia. B.; Ruzmaikin, A. A.; Sokolov, D. D.; Turchaninov, V. I. Bibcode: 1979MoIPM.........Z Altcode: The paper deals with a simple magnetic self-generating dynamo with an asymmetric helicity function in a thin disk. New exact solutions for the steady-state dynamo are obtained, and the properties of known exact solutions are analyzed. The results obtained are of importance to the generation of magnetic fields in the Galaxy and in turbulent disks of the type observed about some X-ray sources. Title: Faraday rotation in galaxies, and absorption lines in quasars Authors: Komberg, B. V.; Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1979SvAL....5...40K Altcode: No abstract at ADS Title: The Nature of One Mechanism of Solar Differential Rotation Authors: Ruzmaikin, A. A.; Vainshtein, S. I. Bibcode: 1978Ap&SS..59..215R Altcode: The mechanism of the solar differential rotation usually ascribed to an anisotropic viscosity action is shown to be caused by Coriolis forces which influence anisotropic convective elements in a stratified medium. The estimation of an anisotropy parameters as a function of the convective zone depth is given. The value of (s-1) is positive near the solar surface and negative at the convective zone base, which is in good agreement with observations and the dynamo theory. Title: Galactic magnetic field parameters determined from Faraday rotation of radio sources Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Kovalenko, A. V. Bibcode: 1978SvA....22..395R Altcode: No abstract at ADS Title: Galactic magnetic field parameters determined from Faraday rotation of radio sources Authors: Ruzmaikin, A. A.; Sokolov, D. D.; Kovalenko, A. V. Bibcode: 1978AZh....55..692R Altcode: No abstract at ADS Title: The Magnetic Field Transfer in the Solar Convective Zone Authors: Ruzmaikin, A. A.; Vainshtein, S. I. Bibcode: 1978Ap&SS..57..195R Altcode: The large-scale azimuth magnetic field is pumping to the bottom of the solar convective zone due to the diamagnetic action of turbulent conductive fluids. When the field at the bottom is of about 103 G, an equilibrium is established between diamagnetic pumping and buoyancy. If, in addition to the density gradient, an additional anisotropy exists (for instance, due to rotation), another mechanism of the magnetic field transfer appears, the efficiency of which greatly depends on the magnitude of the anistropy parameter. Title: Erratum: "The scale and strength of the galactic magnetic field according to the pulsar data" [Astrophys. Space Sci., Vol. 52, p. 365 - 374, 374 - 385 (1977)]. Authors: Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1978Ap&SS..56..519R Altcode: No abstract at ADS Title: A method for determining the large-scale magnetic field in the solar corona Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1978PAZh....4...23R Altcode: A method is developed for determining the magnetic field in the solar corona from observations of the Faraday rotation of many discrete radio sources projected against the corona. With this method the averaged characteristics of the coronal magnetic field and electron density can be obtained by using Tikhonov's (1963) method to solve a Fredholm integral equation of the first kind. The observations required to implement the proposed method are discussed, and a simple estimate of the expected solution is examined. A list of 42 extragalactic radio sources and pulsars which 'pass through' the corona at an angular distance of no more than 5 deg from the center of the sun is given. Title: A method for determining the large-scale magnetic field in the solar corona Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1978SvAL....4...12R Altcode: No abstract at ADS Title: The galaxy magnetic field Authors: Ruzmaikin, A. A. Bibcode: 1978cdeo.coll...73R Altcode: 1978IAUCo..45...73R; 1977cdeo.coll...73R The paper considers the dynamo theory for the generation of the Galactic magnetic field. The Galactic dynamo model contains two mechanisms which act simultaneously: (1) the stretching of the azimuth field away from the meridional field due to differential rotation, and (2) the generation of a meridional component from the azimuth field by means of helical turbulence. Magnetic field generation is discussed with reference to certain problems of Galactic dynamics and evolution. Title: The Scale and Strength of the Galactic Magnetic Field According to the Pulsar Data (In Russian) Authors: Ruzmaikin, A. A.; Sokoloff, D. D. Bibcode: 1977Ap&SS..52..375R Altcode: No abstract at ADS Title: The Scale and Strength of the Galactic Magnetic Field According to the Pulsar Data Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1977Ap&SS..52..365R Altcode: In accordance with the data on the Faraday rotation, angular coordinates, and dispersion measurements and distances of 38 pulsars, the strengthB=2.1±1.1 μG and directionl=99°±24°,b≅0° of the large-scale galactic magnetic field and the mean electron density in the galactic discN e=0.03±0.01 cm-3 are determined. A comparison with the results of a study of the measures of rotation of extragalactic radio sources enabled us to estimate the characteristic half-width of the distribution of the electron density on the Z-coordinate (h≅400 ps). The characteristic size of galactic magnetic field flucturations is shown to be ℒ=100 150 ps. Title: A nonlinear magnetohydrodynamic model of the solar dynamo Authors: Ivanova, T. S.; Ruzmaikin, A. A. Bibcode: 1977AZh....54..846I Altcode: A numerical solution is developed for the simplest nonlinear MHD dynamo model of large-scale magnetic-field generation in the solar convection zone. The nonlinearity is introduced by varying the form of the function that describes the helicity of the velocity field. As a result, growing oscillations are suppressed, and a steady-state solution is obtained for a given period and amplitude. Phase relations between the meridional and azimuthal magnetic-field components are examined, a limit is placed on the dependence of angular velocity on convection-zone depth, and a butterfly diagram in qualitative agreement with the observed diagram is plotted. Estimates of the steady-state dynamo number, period, and amplitude are also found to be in good agreement with observations. Title: A nonlinear magnetohydrodynamic model of the solar dynamo Authors: Ivanova, T. S.; Ruzmaikin, A. A. Bibcode: 1977SvA....21..479I Altcode: A numerical solution is developed for the simplest nonlinear MHD dynamo model of large-scale magnetic-field generation in the solar convection zone. The nonlinearity is introduced by varying the form of the function that describes the helicity of the velocity field. As a result, growing oscillations are suppressed, and a steady-state solution is obtained for a given period and amplitude. Phase relations between the meridional and azimuthal magnetic-field components are examined, a limit is placed on the dependence of angular velocity on convection-zone depth, and a butterfly diagram in qualitative agreement with the observed diagram is plotted. Estimates of the steady-state dynamo number, period, and amplitude are also found to be in good agreement with observations. Title: The interpretation of rotation measures of extragalactic radio sources. Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1977A&A....58..247R Altcode: The Galactic, intrinsic source, and intergalactic-magnetic-field contributions to the observed rotation measures (RM) of extragalactic radio sources are studied simultaneously in the framework of a simple model in which the observed RM is represented as the sum of these three contributions. A regression method is used to obtain the model parameters as well as information on the magnitude of possible selection and evolutionary effects. The analysis is applied to selected extragalactic radio sources listed in three basic catalogs; it is found that the value of the Galactic contribution is practically independent of redshift and the mass density of the universe, while the intergalactic-magnetic-field contribution is insignificant. The magnitude of the large-scale Galactic magnetic field is estimated to be about 4.5 microgauss, and it is concluded that there is no definite evidence for the existence of a homogeneous intergalactic magnetic field. Title: Anisotropic cosmological solutions in the gravitational theory with quadratic invariants. Authors: Ruzmaikin, A. A. Bibcode: 1977Afz....13..345R Altcode: It is noted that quantum modifications of the general-relativistic equations near the cosmological singularity can be partially achieved by adding terms in the square of the curvature tensor to the Lagrangian of the gravitational field. Such a modified theory is found to yield solutions with a regular minimum at t = 0 in the general anisotropic case. However, analysis of the simplest homogeneous and anisotropic metric indicates that these solutions are not characterized by power-law asymptotic behavior as t tends to infinity. It is shown that allowance for certain logarithmic terms in the curvature tensor alters the situation slightly, at least in the isotropic case. It is concluded that effects of particle production and possibly of nonlocal terms must be taken into account in a self-consistent manner in order to resolve the question of whether the cosmological singularity can be eliminated by a transformation to power-law behavior. Title: Anisotropic cosmological solutions in the theory of gravitation with quadratic invariants Authors: Ruzmaikin, A. A. Bibcode: 1977Ap.....13..186R Altcode: No abstract at ADS Title: Nonhomogeneous large-scale magnetic field and the global structure of the universe. Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1977Afz....13...95R Altcode: Previous analysis of observational data on the Faraday rotation of radio emission from extragalactic sources has indicated the existence of a large-scale universal magnetic field. This paper proposes that that large-scale field is associated with the topological structure of the universe. It is assumed that the observed anisotropies in topological gluing and field direction have a common origin and that the characteristic scale of the magnetic field determines the scale of gluing. It is shown that a specific pattern of source 'ghosts' arises in such a model and can be observed in principle. Title: Inhomogeneous large-scale magnetic field and global structure of the Universe Authors: Ruzmaikin, A. A.; Sokolov, D. D. Bibcode: 1977Ap.....13...50R Altcode: No abstract at ADS Title: The Accretion of Matter by a Collapsing Star in the Presence of a Magnetic Field. II: Self-consistent Stationary Picture Authors: Bisnovatyi-Kogan, G. S.; Ruzmaikin, A. A. Bibcode: 1976Ap&SS..42..401B Altcode: The stationary two-dimensional magnetohydrodynamic solution for the accretion of the matter without pressure into a gravitating centre of a black hole is obtained. It is assumed that the magnetic field far from the collapsed star is homogeneous and its influence on the flow is negligible. Around the star, at the plane perpendicular to the direction of the magnetic field, the dense quasistationary disc is formed, the structure of which in a large extent is determined by dissipation processes. The structure is calculated for (a) a laminar disc with the Coulomb mechanism of dissipation; and (b) a turbulent disc. The estimations of the parameters of the shock which result from the infall of the matter onto the disc are given. In the last section the numerical estimation and approximate character of the radiation spectrum of the disc and the shock are obtained for two cases of 10M ⊙ and 105 M ⊙. The luminosity of collapsed objects withM=10M ⊙ appears to be about solar, thus its observation is possibly only at the distances less than 300 1000 pc. The collapsed objects in the Galaxy withM=105 M ⊙ could constitute very bright sources in spectral regions from optical up to X-ray. The spectra of a laminar and a turbulent disc for 10M ⊙ black hole are very different. The laminar disc radiates primarily in the ultraviolet. The turbulent disc radiates a large part of its flux in the infrared. Therefore, one cannot exclude the possibility that some of the galactic infrared star-like sources are individual black holes in the accretion state. Title: The Accretion of Matter by a Collapsing Star in the Presence of a Magnetic Field. II: Self-consistent Stationary Picture (In Russian) Authors: Bisnovatyi-Kogan, G. S.; Ruzmaikin, A. A. Bibcode: 1976Ap&SS..42..375B Altcode: No abstract at ADS Title: Possible evaluation of the magnetic field near pulsars from the beat frequency of atomic transitions Authors: Ruzmaikin, A. A. Bibcode: 1976SvA....19..702R Altcode: For the determination of the magnetic field in astrophysical conditions the use of the 'beats' effect in the atomic transitions is suggested. The frequency of beats under the Zeeman split is proportional to the magnetic field; its Doppler spread is negligible. The synphase excitation of atoms can be accomplished by means of the short pulse of the linear polarized light. The concrete estimations are made for the case of the forbidden lines in the Crab nebula excited by the optic pulse of the pulsar NP 0531. Title: Astrophysical magnetic fields determined from polarization by atomic fluorescence Authors: Ruzmaikin, A. A. Bibcode: 1976AZh....53..550R Altcode: It is noted that the polarization of resonance radiation is very sensitive to the effect of external magnetic fields and that interference between the Zeeman components of such radiation for quasi-degenerate levels yields a linearly polarized line with a rotating plane of polarization, provided the exciting light has a broad spectrum. Polarization of resonance radiation in a weak magnetic field is analyzed, and it is shown that the rotation angle and the degree of polarization are determined by the magnetic-field intensity. Possibilities of applying this effect as a method for determining the magnetic fields of astrophysical objects are considered. The magnitude of the effect is estimated for several forbidden lines of the solar corona and Seyfert galaxy nuclei as well as for some cometary molecular and atomic lines. Title: Astrophysical magnetic fields determined from polarization by atomic fluorescence Authors: Ruzmaikin, A. A. Bibcode: 1976SvA....20..311R Altcode: No abstract at ADS Title: A Magnetohydrodynamic dynamo model of the solar cycle Authors: Ivanova, T. S.; Ruzmaikin, A. A. Bibcode: 1976SvA....20..227I Altcode: No abstract at ADS Title: A Magnetohydrodynamic dynamo model of the solar cycle Authors: Ivanova, T. S.; Ruzmaikin, A. A. Bibcode: 1976AZh....53..398I Altcode: The hydromagnetic-dynamo model of the cyclic process in the sun's convective zone, in which differential rotation and gyrotropic turbulent convective motions play the main role, is investigated. The employed difference method for the numerical solution of the basic equations of magnetic-field generation allows the system of unsteady partial differential equations to be solved without reducing it to the eigenvalue problem. The principal results are the following: (1) an oscillatory solution in the quadrupole mode is obtained; (2) it is shown that the period of the oscillations and the critical dynamo number essentialy depend on the jump in the conductivity at the boundary between the convective zone and the radiative nucleus as well as on the diamagnetism of the convective zone. In particular, the diamagnetic effect can strongly increase the period of the oscillations. Title: Possible evaluation of the magnetic field near pulsars from the beat frequency of atomic transitions Authors: Ruzmaikin, A. A. Bibcode: 1975AZh....52.1173R Altcode: For the determination of the magnetic field in astrophysical conditions the use of the 'beats' effect in the atomic transitions is suggested. The frequency of beats under the Zeeman split is proportional to the magnetic field; its Doppler spread is negligible. The synphase excitation of atoms can be accomplished by means of the short pulse of the linear polarized light. The concrete estimations are made for the case of the forbidden lines in the Crab nebula excited by the optic pulse of the pulsar NP 0531. Title: Collisionless generation of rotation in galaxies Authors: Ruzmaikin, A. A. Bibcode: 1975PAZh....1...10R Altcode: No abstract at ADS Title: Collisionless generation of rotation in galaxies Authors: Ruzmaikin, A. A. Bibcode: 1975SvAL....1...95R Altcode: No abstract at ADS Title: Determination of astrophysical magnetic fields from the polarization of atomic fluorescence Authors: Ruzmaikin, A. A. Bibcode: 1975MoIPM.........R Altcode: It is well known that polarization of atomic fluorescence is sensitive to the action of weak magnetic fields. In the case of excitation by light with a wide spectrum, the interference of the Zeeman components for a quasi-degenerate level gives a linearly polarized line with a rotating polarization plane. The angle of rotation and the degree of polarization are defined by the magnitude of the magnetic field. The aim of the present book is to give a physically acceptable description of this effect, and to examine various means of using it to determine astrophysical magnetic fields. Title: The Accretion of Matter by a Collapsing Star in the Presence of a Magnetic Field Authors: Bisnovatyi-Kogan, G. S.; Ruzmaikin, A. A. Bibcode: 1974Ap&SS..28...45B Altcode: The exact nonstationary solution for the variation of the magnetic field in the Schwarzschild metric with a given spherically symmetric flow is obtained. Initially a homogeneous magnetic field increases with time, changing into a quasi-radial field. On the assumption of equipartition between the magnetic and kinetic energies of a falling gas, in the relativistic case, estimates of the stationary field and the intensity of synchrotron radiation are presented. A considerable part of the radiation is formed in the relativistic regionr≲(2.5 to 7.7)r g (r g is the gravitational radius of a black hole). Estimates are made for radiation from the relativistic region in the case of disc type accretion. Title: The Accretion of Matter by a Collapsing Star in the Presence of a Magnetic Field (In Russian) Authors: Bisnovatyi-Kogan, G. S.; Ruzmaikin, A. A. Bibcode: 1974Ap&SS..28...31B Altcode: No abstract at ADS Title: The Stability of Rotating Supermassive Stars Authors: Bisnovaty-Kogan, G. S.; Ruzmaikin, A. A. Bibcode: 1973A&A....27..209B Altcode: Summary. Supermassive stars (those with M> 10 M0) are maintained in equilibrium by their radiation pressure. However, when first order general relativistic effects are taken into account, such stars are seen to be unstable against collapse, and rotation can become the most important means of establishing their stability: in this paper this is investigated by adding to the usual expressions for the full mass-energy, rest mass and angular momentum deviations arising from the second order post-newtonian corrections of general relativity in stationary, rotating configurations. These corrections are obtained by expanding the exact Einstein expressions to order 1/c4. The approximate "energy" method is then used to study stability against collapse; the energy functional is written in terms of two parameters - Qc, the central density, and cc, a measure of oblateness - and its first and second variations define the state of the star. When the first variation vanishes, the star is in equilibrium, and if the second is positive it is also stable. We have found that: J2> J? =0.19 ( 2GcMO2 )2 leads to stable equilibrium: when J? <J2 <J22 =0.35 (2GcMO2 )2 the star in the course of time becomes unstable against collapse: when j2 > J22 the star eventually forms itself into a thin disc. Our results are applied to a model of a quasar Key words: general relativity - post-newtonian corrections - stability Title: Star Contraction and Magnetic-Field Generation in Protogalaxies. Authors: Bisnovatyi-Kogan, G. S.; Ruzmaikin, A. A.; Syunyaev, R. A. Bibcode: 1973SvA....17..137B Altcode: No abstract at ADS Title: Relativistic Vortex Motion Authors: Vainshtein, S. I.; Ruzmaikin, A. A. Bibcode: 1973SvA....17....7V Altcode: No abstract at ADS Title: Relativistic Vortex Motion Authors: Vainshtein, S. I.; Ruzmaikin, A. A. Bibcode: 1973AZh....50...12V Altcode: No abstract at ADS Title: Star Contraction and Magnetic-Field Generation in Protogalaxies. Authors: Bisnovatyi-Kogan, G. S.; Ruzmaikin, A. A.; Syunyaev, R. A. Bibcode: 1973AZh....50..210B Altcode: No abstract at ADS Title: Generation of the Large-Scale Galactic Magnetic Field. II. Authors: Vainshtein, S. I.; Ruzmaikin, A. A. Bibcode: 1972SvA....16..365V Altcode: No abstract at ADS Title: Generation of the Large-Scale Galactic Magnetic Field. Authors: Vainshtein, S. I.; Ruzmaikin, A. A. Bibcode: 1972SvA....15..714V Altcode: No abstract at ADS Title: Generation of the Large-Scale Galactic Magnetic Field. II. Authors: Vainshtein, S. I.; Ruzmaikin, A. A. Bibcode: 1972AZh....49..449V Altcode: No abstract at ADS Title: On the Generation of Magnetic Field in Rotating Relativistic Objects Authors: Bisnovaty-Kogan, G. S.; Ruzmaikin, A. A. Bibcode: 1972A&A....17..243B Altcode: It is shown that there is no magnetic field generation in a stationary rotating relativistic star if Q = const in the case of a barotropic medium and in an isentropic star with Q const. Key words: rotation - relativity - magnetic field generation Title: Generation of the Large-Scale Galactic Magnetic Field. Authors: Vainshtein, S. I.; Ruzmaikin, A. A. Bibcode: 1971AZh....48..902V Altcode: No abstract at ADS Title: Gravitational Stability of an Expanding Universe in the Presence of a Magneric Field. Authors: Ruzmaikina, T. V.; Ruzmaikin, A. A. Bibcode: 1971SvA....14..963R Altcode: No abstract at ADS Title: Gravitational Stability of an Expanding Universe in the Presence of a Magneric Field. Authors: Ruzmaikina, T. V.; Ruzmaikin, A. A. Bibcode: 1970AZh....47.1206R Altcode: No abstract at ADS Title: The story told by the anisotropy of the relict radiation. Authors: Ruzmaikin, A. A. Bibcode: 1970Prir....5...68R Altcode: No abstract at ADS