Author name code: smaldone ADS astronomy entries on 2022-09-14 author:"Smaldone, Luigi A." ------------------------------------------------------------------------ Title: Quantum groups and polymer quantum mechanics Authors: Acquaviva, G.; Iorio, A.; Smaldone, L. Bibcode: 2021MPLA...3650229A Altcode: 2021arXiv210514792A In Polymer Quantum Mechanics, a quantization scheme that naturally emerges from Loop Quantum Gravity, position and momentum operators cannot be both well defined on the Hilbert space (ℋPoly). It is henceforth deemed impossible to define standard creation and annihilation operators. In this paper, we show that a q-oscillator structure, and hence q-deformed creation/annihilation operators, can be naturally defined on ℋPoly, which is then mapped into the sum of many copies of the q-oscillator Hilbert space. This shows that the q-calculus is a natural calculus for Polymer Quantum Mechanics. Moreover, we show that the inequivalence of different superselected sectors of ℋPoly is of topological nature. Title: Bekenstein bound from the Pauli principle Authors: Acquaviva, G.; Iorio, A.; Smaldone, L. Bibcode: 2020PhRvD.102j6002A Altcode: 2020arXiv200513973A Assuming that the degrees of freedom of a black hole are finite in number and of fermionic nature, we naturally obtain, within a second-quantized toy model of the evaporation, that the Bekenstein bound is a consequence of the Pauli exclusion principle for these fundamental degrees of freedom. We show that entanglement, Bekenstein, and thermodynamic entropies of the black hole all stem from the same approach, based on the entropy operator whose structure is the one typical of Takahashi and Umezawa's thermofield dynamics. We then evaluate the von Neumann black hole-environment entropy and noticeably obtain a Page-like evolution. We finally show that this is a consequence of a duality between our model and a quantum dissipativelike fermionic system. Title: Information entropy in solar atmospheric fields. I. Intensity photospheric structures Authors: Consolini, G.; Berrilli, F.; Florio, A.; Pietropaolo, E.; Smaldone, L. A. Bibcode: 2003A&A...402.1115C Altcode: The existence of a quasi-regular pattern in solar photospheric convective fields is an open question. In the present work, this problem is quantitatively approached by means of the normalised information entropy measure H'(r) as introduced by Van Siclen (\cite{VanSic97}), which reports on the information content at different scales. Images were acquired at the THEMIS telescope of the European Northern Observatory by the IPM observing mode, and at the Richard B. Dunn Solar Telescope of the National Solar Observatory. The evaluation of H'(r) in the case of photospheric intensity binarized images shows the presence of maxima which are evidence of different prominent scales in the photospheric pattern. The relative positions of these maxima defines an ordering scale ~ 1.6 Mm in both instantaneous and average images. This is read as the evidence of a spatio-temporal organization in the evolution of convective pattern. The emergence of an ordering scale is discussed in the framework of pattern formation in random systems and in connection with the findings of previous works. By averaging images with time, an increase of the information content characterized by a coherence time of ~ 1 h is observed in the range of scales from 5.0 Mm to 10.0 Mm. Title: Solar and Heliospheric Observatory/Coronal Diagnostic Spectrograph and Ground-based Observations of a Two-Ribbon Flare: Spatially Resolved Signatures of Chromospheric Evaporation Authors: Teriaca, L.; Falchi, A.; Cauzzi, G.; Falciani, R.; Smaldone, L. A.; Andretta, V. Bibcode: 2003ApJ...588..596T Altcode: During a coordinated observing campaign (Solar and Heliospheric Observatory, SOHO JOP 139), we obtained simultaneous spectroheliograms of a solar active region in several spectral lines, sampling levels from the chromosphere to the corona. Ground-based spectroheliograms were acquired at the Dunn Solar Tower of the National Solar Observatory/Sacramento Peak in four chromospheric lines, while the coronal diagnostic spectrograph on board SOHO was used to obtain rasters of the active region in transition region (TR) and coronal lines. Such a complete data set allowed us to compare the development of intensity and velocity fields during a small two-ribbon flare in the whole atmosphere. In particular, we obtained for the first time quasi-simultaneous and spatially resolved observations of velocity fields during the impulsive phase of a flare, in both the chromosphere and upper atmosphere. In this phase, strong downflows (up to 40 km s-1) following the shape of the developing ribbons are measured at chromospheric levels, while strong upward motions are instead measured in TR (up to -100 km s-1) and coronal lines (-160 km s-1). The spatial pattern of these velocities have a common area about 10" wide. This is the first time that opposite-directed flows at different atmospheric levels are observed in the same spatial location during a flare. These signatures are highly suggestive of the chromospheric evaporation scenario predicted in theoretical models of flares. Title: Mass Motions in a Young Active Region Authors: Cauzzi, G.; Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 2003MmSAI..74..659C Altcode: We present an observational program devoted to the study of dynamic phenomena at small spatial and temporal scales throughout the solar atmosphere, with special attention to chromospheric events that have an impact on the coronal structure. On the one hand, we show the existence of flare signatures in the chromosphere at the smallest scales, supporting the idea that (micro)flares represent a viable mechanism for supply of heat and mass to the corona. On the other, such events are quite scarce in our dataset, while much more common are surge-like events, occurring repeatedly in the same locations and visible both in the chromosphere and the corona, and that do not display obvious flare signatures. Title: Spatially resolved signatures of chromospheric evaporation during a small two-ribbon flare Authors: Teriaca, L.; Falchi, A.; Cauzzi, G.; Falciani, R.; Smaldone, L. A.; Andretta, V. Bibcode: 2003MmSAI..74..635T Altcode: Ground based spectroheliograms of a solar active region were acquired in four chromospheric lines simultaneously with rasters in transition region (TR) and coronal lines obtained with the Coronal Diagnostic Spectrograph (CDS) aboard SOHO. Such a complete dataset allows us to study the development of intensity and velocity fields during a small two-ribbon flare in the whole atmosphere. In particular, we obtain for the first time quasi-simultaneous and spatially resolved observations of velocity fields during the impulsive phase of a flare, both in chromosphere and upper atmosphere. In this phase, strong downflows (up to 40 km s-1) following the shape of the developing ribbons are measured at chromospheric levels, while strong upward motions are measured in TR (up to -100 km s-1) and coronal lines (-160 km s-1). The spatial pattern of these velocities have a common area about 10 arcsec wide. This is the first time that opposite directed flows at different atmospheric levels are observed in the same spatial location during a flare. These signatures are highly suggestive of the chromospheric evaporation scenario predicted in theoretical models of flares. Title: CONCORDIASTRO/Italy: A Solar High-Resolution Observation Program at Dome-C Authors: Severino, G.; Andretta, V.; Berrilli, F.; Cascone, E.; Centrone, M.; Criscuoli, S.; Del Moro, D.; Ermolli, I.; Giorgi, F.; Jefferies, S. M.; Magri, M.; Moretti, P. F.; Oliviero, M.; Parisi, L.; V; Porzio; Smaldone, L. A.; Straus, Th. Bibcode: 2003MSAIS...2..181S Altcode: CONCORDIASTRO is the Nice-Napoli joint project for site testing of the Dome C for solar and stellar astronomy in the visible. CONCORDIASTRO/Italy is the solar physics part of this project, whose the Napoli team has the principal responsibility. Beyond the well-known interest for the helioseismology, CONCORDIASTRO/Italy pointed out that, because of its special atmospheric conditions, Dome C promises to be one of the best sites on Earth to perform high-resolution solar physics. Here we review the basis for this statement and the solar observations program planned by CONCORDIASTRO/Italy. Title: Chromospheric and Transition region He lines during a flare Authors: Falchi, A.; Mauas, P. J. D.; Andretta, V.; Teriaca, L.; Cauzzi, G.; Falciani, R.; Smaldone, L. A. Bibcode: 2003MmSAI..74..639F Altcode: An observing campaign (SOHO JOP 139), coordinated between ground based and SOHO instruments, has been planned to obtain simultaneous spectroheliograms of the same area in several spectral lines. The chromospheric lines Ca II K, Hα and Na I D as well as He I 10830, 5876, 584 and 304 Ålines have been observed. These observations allow us to build semi-empirical models of the atmosphere before and during a small flare. With these models, constructed to match the observed line profiles, we can test the He abundance value. Title: Chromospheric evaporation in a two-ribbon flare Authors: Cauzzi, G.; Falchi, A.; Teriaca, L.; Falciani, R.; Smaldone, L. A.; Andretta, V. Bibcode: 2002ESASP.506..561C Altcode: 2002ESPM...10..561C; 2002svco.conf..561C We present simultaneous, spatially and temporally resolved chromospheric, transition region and coronal observations of a small eruptive flare studied throughout its whole development. We show that strong and co-spatial plasma motions, oppositely directed in the chromosphere (downflows) and in upper atmospheric layers (upflows), develop at the onset of the flare. For the first time, we prove that such oppositely directed flows originate from the same flaring kernels in different atmospheric layers. Using realistic values for the plasma parameters in the flaring loop, we also estimate a balance between the upward and downward momenta. Our observations confirm in a very convincing way the scenario of chromospheric evaporation predicted in theoretical models of flares. Title: Combined space and ground based observations of a C-1 flare Authors: Teriaca, L.; Falchi, A.; Cauzzi, G.; Falciani, R.; Smaldone, L. A.; Andretta, V. Bibcode: 2002ESASP.508..457T Altcode: 2002soho...11..457T We present temporally and spatially resolved space and ground based observations of a C1 flare. Ground based spectroheliograms were acquired at the Dunn Solar Tower of NSO/Sacramento Peak in several chromospheric lines. Simultaneously, the Coronal Diagnostic Spectrograph (CDS) aboard SoHO was used to obtrain rasters of the same active region in transiton region (TR) and coronal lines. This unique dataset provides us, for the first time, with spatially resolved observations of velocity fields during the impulsive phase of the flare, from the chromosphere up to the TR and the corona. At the time of the emission peak, a large area of the flaring kernel observed in TR lines is characterized by upward velocities. A ~6"×6" kernel displays upflows velocity above 80 km s-1. In this same area we found, in data obtained about 3 minutes later, chromospheric downflows of 10 - 20 km s-1. This is the first time that opposite directed flows at different atmospheric levels are observed in the same spatial location during a flare. Title: Foreword (SOLSPA 2001) Authors: Schmieder, Brigitte; Smaldone, Luigi Bibcode: 2002ESASP.477D..15S Altcode: 2002scsw.confD..15S No abstract at ADS Title: Understand spectroheliograms - insight from spectral line analysis Authors: Smaldone, L. A.; Scognamiglio, O.; Balasubramaniam, K. S. Bibcode: 2001MmSAI..72..553S Altcode: In an effort to seek newer diagnostic tools for monitoring the solar activity, we have reconstructed spectroheliograms in various spectral lines in the range 3900-3940 Angstroms (around the Ca II K line), from high spatial and spectral resolution measurements. In active regions, we find that the spectroheliogram features in a number of spectral lines are similar to the Ca II K1v spectroheliogram features. In plages, on the contrary, only spectroheliograms in a few spectral lines correlate with the Ca II K1v. In plages, we get the best correlation with the Si I 3905. From these measurements we develop contrast functions to isolate various active phenomena as seen in Ca II, and compare its formation contribution of relative velocities, magnetic fields and intensity as seen in Fe I and Si I spectral lines. These indicators provide much insight into the formation of Ca II K line. Title: A chromospheric model for FU Ori Authors: D'Angelo, G.; Errico, L.; Gomez, M. T.; Smaldone, L. A.; Teodorani, M.; Vittone, A. A. Bibcode: 2000A&A...356..888D Altcode: We present medium and high-dispersion optical spectra of the FUOr variable FU Ori, demonstrating that some lines are subject to variability both on a yearly and on a daily time scale. Some raw models of accretion disk atmospheres are presented in order to explain both qualitatively and quantitatively the dynamics of the observed line variability. Computing synthetic profiles for the Hα line by using the non-LTE MULTI code, we find that the emission component of this feature is very sensitive to the temperature gradient and the maximum temperature reached in a chromospheric-like layer. Further, the blue absorption component of the Hα depends only on the velocity field of the wind and the transition between the absorption and emission components is produced where the chromosphere ends and the wind begins. Similar chromospheric analysis is applied to the profile of the Na I D lines in pure absorption. Title: FU Orionis: an accretion disk with an active chromosphere ? Authors: D'Angelo, G.; Gomez, M. T.; Errico, L.; Smaldone, L. A.; Vittone, A. A. Bibcode: 2000MmSAI..71.1037D Altcode: No abstract at ADS Title: Wavelet Analysis of Spatial Coherent Structures in the Photosphere Authors: Pietropaolo, E.; Berrilli, F.; Consolini, G.; Smaldone, L. A.; Straus, T.; Cauzzi, G.; Bruno, R.; Bavassano, B. Bibcode: 1999ESASP.448..343P Altcode: 1999ESPM....9..343P; 1999mfsp.conf..343P No abstract at ADS Title: Simultaneous 2-D Spatial Spectra Using a Microlens Array Authors: Balasubramaniam, K. S.; Suematsu, Y.; Smaldone, L. A.; Yoshimura, K.; Hegwer, S.; Otani, H. Bibcode: 1999AAS...194.9306B Altcode: 1999BAAS...31R.989B Simultaneous spatial spectra of extended solar structures, at a high spatial resolution and temporal cadence is important to track and understand the physics of dynamical evolutionary phenomena. Replacing the slit of a conventional spectrograph with a micro-lens array will then help to capture simultaneous spatial spectra using a large format CCD camera. Such a technique will be useful to study small structures (a few arcseconds across) such as Ellerman bombs, kernels of flares, filamentary evolution and spicules. At the NSO/Richard B. Dunn Solar Telescope, we have used a micro-lens array (0.6 mm pitch, 50 x 50 lens-lets) to observe structures with a spatial sampling of 0.24 arcseconds in Hα \ spectral line. The spectral sampling is 0.93 Angstroms/pixel over a 10- Angstroms bandwidth. The field-of-view is however limited to about 12 arcseconds. We have also explored the microlens array the observations to magnetic spectral lines such as FeI 6301.5 and FeI 6302.5 Angstroms for variation of line-of-sight of subarcsecond magnetic fields. We present initial results from an engineering observational experiment at the Dunn Solar Telescope. Title: Effects of the Spectral and Spatial Resolution on the Detection of K2v Grains Authors: Smaldone, L.; Salvatore, A. Bibcode: 1999ASPC..183..412S Altcode: 1999hrsp.conf..412S No abstract at ADS Title: Velocities in Solar Pores Authors: Keil, S. L.; Balasubramaniam, K. S.; Smaldone, L. A.; Reger, B. Bibcode: 1999ApJ...510..422K Altcode: We use high spatial and spectral resolution filtergrams to examine the three-dimensional morphology and velocity fields associated with solar pores in a region of newly emerged magnetic flux. The observed amplitude of the horizontal surface velocities decreases near the pores. Most of the pores exhibit a downflow in the surrounding region. Time-averaged line-of-sight velocities in and near the pores increased with the strength of the associated magnetic field. The LOS velocities are such that the maximum downflow is not centered about the continuum intensity and sometimes traces an annulus ringlike structure around the pore. From a time sequence of continuum images, it appears that some pores shed flux at the photospheric level. ``Cork movies'' of the surface velocities show that the ``corks'' are advected toward weak downflows near the pore locations and that the loci of the advected corks trace boundaries that resemble mesogranular and supergranular flows. We analyze the vertical velocity structure in pores and show that the downflow decreases exponentially with height, with a scale height that is a factor of 2 smaller than the photospheric scale height for granules. The line-of-sight flow associated with the pores appears to expand with height. Our observations are compared with previous measurements of flows in and around pores that were based on both spectrograms and filtergrams. Finally, we provide a phenomenological description for pores. Title: Chromospheric K2v grains properties Authors: Salvatore, A.; Smaldone, L. A. Bibcode: 1998MmSAI..69..639S Altcode: No abstract at ADS Title: The Wind of FU Orionis: Modelling the Atmosphere Authors: D'Angelo, G.; Errico, L.; Gomez, M. T.; Smaldone, L. A.; Teodorani, M.; Vittone, A. A. Bibcode: 1998cvsw.conf..323D Altcode: No abstract at ADS Title: Properties of solar granulation cells in quiet regions as derived from a time series of white light images Authors: Cauzzi, G.; Consolini, G.; Berrilli, F.; Smaldone, L. A.; Straus, T.; Bavassano, B.; Bruno, R.; Caccin, B.; Carbone, V.; Egidi, A.; Ermolli, I.; Florio, A.; Pietropaolo, E. Bibcode: 1998MmSAI..69..647C Altcode: No abstract at ADS Title: The Magneto-Optical Filter in Napoli: Perspectives and Test Observations Authors: Moretti, P. F.; Severino, G.; Cauzzi, G.; Reardon, K.; Straus, T.; Cacciani, A.; Marmolino, C.; Oliviero, M.; Smaldone, L. A. Bibcode: 1997ASSL..225..293M Altcode: 1997scor.proc..293M An observing station based on the Magneto-Optical-Filter (MOF) technology is being installed at Osservatorio Astronomico di Capodimonte, in Napoli. In this paper, the main characteristics and goals of this new instrument are discussed, and several velocity and magnetic observations from a test campaign are shown. Title: Active region effects on solar irradiance at NA I D lines Authors: Marmolino, C.; Oliviero, M.; Severino, G.; Smaldone, L. A. Bibcode: 1997A&AS..125..381M Altcode: The possibility to detect solar oscillations in the low frequency domain depends crucially on the power contrast among the oscillation signal and other time dependent signals in the same frequency range. The signal to noise ratio is increased by our ability to understand and remove solar sources of noise. In measurements of the mean Doppler velocity shift of the integrated solar disk, the solar noise has a line component spectrum with a major peak at 13.1 days, and a second less prominent peak at 27.2 days. Active region modulation is believed almost completely responsible for this signal. We develop simulations of the flux and velocity fluctuations produced by different solar active region distributions, based on an analytical description of their action. From a grid of models of active regions and from their spatial distribution over the disk, we calculate the synthetic flux profile in the Na I D1 line and determine the velocity measure of a resonance spectrometer. Our velocity results are compared with the offset velocities from the IRIS network. There is a rather good agreement between the observed and computed velocities, and the plage contribution to the noise appears to be dominant. The simulation allows to test calibration procedures and to study the effect on the spurious velocities of different parameters, such as the intensity thresholds used to determine the areas of spots and plages, and the contrast of the active regions. In particular, we find that the inclusion of intrinsic line shifts in plages can change strongly both the amplitude and the shape of the simulated signal, and then may be an important source of uncertainty for the simulation. Title: Multispectral Observations of AN Eruptive Flare Authors: Qiu, J.; Falchi, A.; Falciani, R.; Cauzzi, G.; Smaldone, L. A. Bibcode: 1997SoPh..172..171Q Altcode: 1997ESPM....8..171Q We analyze the pre-flare and impulsive phase of an eruptive (two-ribbon) flare at several wavelengths. The total energy (mechanical plus radiative) released by the flare is 8 x 1030 erg, about a factor 6 higher than the free magnetic energy (1.3 1030 erg) estimated from the non-potentiality of the magnetic field configuration in the flare area. During the impulsive phase, we find a very good time coincidence between the hard X-ray light curve and the light curves for 2 small areas (≃ 4″ in size) in the red wing of the Hα line and in the He-D3 line center. This temporal coincidence is compatible with the interpretation that hard X-ray emission is produced by bremsstrahlung of accelerated electron beams striking these dense areas. For the other regions of the Hα ribbons we find more gradual light curves, suggesting a different energy transport mechanism such as conduction. Title: Dynamics of Minor Solar Activity \newline Coordinated Observations SOHO-GBO JOP #37 Authors: Cauzzi, G.; Vial, J. C.; Falciani, R.; Falchi, A.; Smaldone, L. A. Bibcode: 1997ASPC..118..309C Altcode: 1997fasp.conf..309C We present a program for coordinated observations between ground based observatories, mainly NSO/Sacramento Peak, and several instruments onboard SOHO (primarily SUMER). The scientific goal is the study of small activity phenomena, at high spatial and temporal resolution. Title: ARTHEMIS: The archive project for the Italian Panoramic Monochromator Authors: Reardon, K.; Severino, G.; Cauzzi, G.; Gomez, M. T.; Straus, T.; Russo, G.; Smaldone, L. A.; Marmolino, C. Bibcode: 1997MmSAI..68..499R Altcode: No abstract at ADS Title: Simultaneous Doppler and magnetic solar maps from a MOF installed at the Osservatorio di Capodimonte Authors: Cacciani, A.; Marmolino, C.; Moretti, P. F.; Oliviero, M.; Severino, G.; Smaldone, L. A. Bibcode: 1997MmSAI..68..467C Altcode: No abstract at ADS Title: Velocities in Solar Pores Authors: Balasubramaniam, K. S.; Keil, S. L.; Smaldone, L. A. Bibcode: 1996AAS...188.0203B Altcode: 1996BAAS...28..820B We investigate the three dimensional structure of solar pores and their surroundings using high spatial and spectral resolution data. We present evidence that surface velocities decrease around pores with a corresponding increase in the line-of-sight (LOS) velocities. LOS velocities in pores increase with the strength of the magnetic field. Surface velocities show convergence toward a weak downflow which appear to trace boundaries resembling meso-granular and super granular flows. The observed magnetic fields in the pores appear near these boundaries. We analyze the vertical velocity structure in pores and show that they generally have downflows decreasing exponentially with height, with a scale height of about 90 km. Evidence is also presented for the expanding nature of flux tubes. Finally we describe a phenomenological model for pores. This work was supported by AFOSR Task 2311G3. LAS was partially supported by the Progetto Nazionale Astrofisica e Fisica Cosmica of MURST and Scambi Internazionali of the Universita degli Studi di Napoli Frederico II. National Solar Observatory, NOAO, is operated for the National Science Foundation by AURA, Inc. Title: Coordinated observations of solar activity phenomena. II. The velocity field pattern in an elementary flare. Authors: Cauzzi, G.; Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1996A&A...306..625C Altcode: We present the line-of-sight velocity pattern determined from spectra obtained before and during a small flare, whose emission properties have been studied in Cauzzi et al. (1995, Paper I). The flare hard X-ray (HXR) emission, in the range 25-100keV, consists of five separate and short spikes (lasting 1-7s), which suggests that this flare is a sequence of separate elementary bursts. 40 seconds before the occurrence of any HXR emission the flare kernel is already bright in Halpha_+1.5A and shows a typical chromospheric flare spectrum with Balmer lines in emission up to H_13_. Also, few seconds before the impulsive phase of the flare (as marked by the occurrence of the first HXR spike) an upward motion is determined from lines originating in high chromospheric layers (CaII K and Hdelta_) and from metallic lines (Si I 3905, Fe I multiplets 4 and 5). These motions together with a simultaneous strong emission suggest that the early chromospheric modifications, which may be considered as signatures of flare precursor, are due to some in situ mechanisms. 6 seconds after the peak time of the first HXR spike we determine a downward velocity, ranging from 1km/s for the metallic lines up to 20km/s for Hdelta_ and CaII K lines, for all the points of the slit intersecting the Halpha_+1.5A kernel. According to the known dynamic flare models, the measured velocity can be explained either by direct heating of the chromosphere from non-thermal electrons with a low energy cutoff of 10keV, or by a thermal conduction front from the hot corona. The downward velocity continues to increase (roughly by a factor of 2) for 10s after the end of the first HXR spike; none of the existing models predicts a similar behavior. After the fourth HXR spike the direction of the velocity changes over the Halpha_+1.5 A kernel and two small regions (=~3" in size), can be distinguished. In the first one a downward velocity of about 15km/s is derived for Hdelta_ and CaII K lines simultaneously to a velocity =~1km/s from the metallic lines. In the second area, the velocities derived from Hdelta_ and CaII K lines are upward directed, with values up to -40km/s, while the velocity derived from the metallic lines is still downward directed, with values =~1km/s. The sudden onset of an upward motion could be related to the development of a surge well visible after the flare; probably only the higher chromospheric layers supply material to the surge. Title: Minor Photospheric and Chromospheric Magnetic Activity and Related Coronal Signatures Authors: Cauzzi, G.; Falchi, A.; Falciani, R.; Hiei, E.; Smaldone, L. A. Bibcode: 1996mpsa.conf..433C Altcode: 1996IAUCo.153..433C No abstract at ADS Title: Active regions effects on global oscillation measurements. Authors: Marmolino, C.; Oliviero, M.; Severino, G.; Smaldone, L. A. Bibcode: 1996joso.proc..160M Altcode: No abstract at ADS Title: Coordinated observations of solar activity phenomena. I. Multispectral study of an elementary flare. Authors: Cauzzi, G.; Falchi, A.; Falciani, R.; Smaldone, L. A.; Schwartz, R. A.; Hagyard, M. Bibcode: 1995A&A...299..611C Altcode: In this paper we present a multispectral analysis of a small flare which may be considered as a sequence of elementary bursts rather than a collective flare phenomenon. A series of 5 short-lived (duration =~1-7s) emission spikes are in fact observed in hard X-ray (HXR). The flare was also observed in soft X-ray (SXR), with 3s temporal resolution, and in the optical range with very high spatial (=~0.5") and temporal (2.7s) resolutions. Sequences of filter images, in Halpha_ +1.5A, He-D_3_ and Na-D_2_ wavelengths were acquired. The flare impulsive phase, indicated by the occurrence of the HXR spikes, is preceded by an enhancement in the chromospheric and in the coronal SXR emissions starting, respectively, 40 and 15s before the flare. This indicates that a density and/or a temperature increase in the flaring loop starts at chromospheric levels, and only after this phase are the 5 separate electron beams sequentially accelerated and stopped in an atmosphere that is already modified. Four of the 5 HXR spikes are temporally associated with chromospheric emission features over small areas of 3" size, while the fifth spike does not have detectable associated signatures. Apparent contradictions between Halpha_ + 1.5 A and He-D_3_ emissions can be explained assuming atmospheric inhomogeneities, already present within the flaring loop. The flare occurs within an area of positive magnetic polarity, which shows a moderate but constant weighted magnetic shear. No inclusions of the opposite polarity are found in the flaring region, and no changes in the distribution of any of the magnetic field parameters are detected before, during and after the flare occurrence. No detectable modifications are measured in the continuum and in all the wavelength points of the Na-D_2_ line profile apart from the line core; this means that flare-associated modifications of the flaring loop atmosphere do not penetrate below the temperature minimum region. Title: Magnetic Noise Simulations in Velocity Authors: Marmolino, C.; Oliviero, M.; Severino, G.; Smaldone, L. A. Bibcode: 1995ESASP.376b.407M Altcode: 1995help.confP.407M; 1995soho....2..407M No abstract at ADS Title: Restored Solar Velocity Measurements Obtained from the May 10, 1994 Annular Solar Eclipse Authors: Keil, S. L.; Balasubramaniam, K. S.; Ljungberg, S. K.; Smaldone, L. A.; Rimmele, T. R. Bibcode: 1995SPD....26..202K Altcode: 1995BAAS...27..951K No abstract at ADS Title: Dynamics of Small Flux Tubes Authors: Reger, Bernard; Keil, Stephen L.; Smaldone, Luigi A.; Cauzzi, Gianna; Balasubramaniam, K. S. Bibcode: 1994ASPC...68..157R Altcode: 1994sare.conf..157R No abstract at ADS Title: Observations of Active Region Dynamics: Preflare Flows and Field Observations Authors: Keil, Stephen L.; Balasubramaniam, K. S.; Bernasconi, Pietro; Smaldone, Luigi A.; Cauzzi, Gianna Bibcode: 1994ASPC...68..265K Altcode: 1994sare.conf..265K No abstract at ADS Title: High temporal and spatial resolution observations of a solar flare on June 7, 1991 Authors: Cauzzi, G.; Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1993AdSpR..13i.311C Altcode: 1993AdSpR..13..311C We present some preliminary results on a small flare observed at the NSO-Sacramento Peak with very good spatial resolution (.6''-.7''). The flare occurred on June, 7 1991 at ~ 13:43 UT in the NOAA region 6659 and has been observed by the COMPTON BATSE experiment in the 25-50 KeV range. A very complex velocity pattern is found for chromospheric and metallic lines: a small region (5'' wide) presents a strong blue-shifts in all these lines, lasting through the flare, while, only in the Ca II-K and Hδ lines, we find a zone (again ~ 5'' wide) of strong red asymmetries contemporary to the hard X-rays spikes. These observations show the importance of having high spatial and temporal resolution measurements in the study of flares. Title: On the calibration of line-of-sight magnetograms Authors: Cauzzi, G.; Smaldone, L. A.; Balasubramaniam, K. S.; Keil, S. L. Bibcode: 1993SoPh..146..207C Altcode: Inference of magnetic fields from very high spatial, spectral, and temporal resolution polarized images is critical in understanding the physical processes that form and evolve fine scale structures in the solar atmosphere. Studying high spectral resolution data also helps in understanding the limits of lower resolution spectral data. We compare three different methods for calibrating the line-of-sight component of the magnetic field. Each method is tested for varying degrees of spectral resolution on both synthetic line profiles computed for known magnetic fields and real data. The methods evaluated are: (a) the differences in the center of gravity of the right and left circular components for different spectral resolution, (b) conversion of circular polarization, at particular wavelengths, to magnetic fields using model-dependent numerical solutions to the equations of polarized radiative transfer, and (c) the derivative method using the weak field approximation. Each method is applied to very high spatial and spectral resolution circular polarization images of an active region, acquired in the FeI 5250 å Zeeman-sensitive spectral line. The images were obtained using the 20 må pass-band tunable filter at NSO/Sacramento Peak Observatory Vacuum Tower Telescope. We find that the center-of-gravity separation offers the best way of inferring the longitudinal magnetic field. Title: Observation of solar flares at high resolution. Authors: Cauzzi, G.; Falciani, R.; Falchi, A.; Smaldone, L. A. Bibcode: 1992ESASP.344..141C Altcode: 1992spai.rept..141C The authors present some preliminary results of the observation of a flare performed at the NSO-Sacramento Peak with very good spatial resolution. The flare occurred on June 7, 1991 at ≡13:43 UT in the NOAA region 6659, showing an unusual high activity. A small region, ≡3″wide, shows strong blue shifts (of the order of the sound speed) in some metallic lines formed in the high photosphere, during the flare impulsive phase. These observations show the importance of having measurements at higher spatial and temporal resolution for an effective improvement of the knowledge of the fundamental dynamic of active regions and flares. Title: Analysis of the optical spectra of the solar flares. VI. Velocity field in the 13 June 1980 flare area. Authors: Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1992A&A...256..255F Altcode: The 13 June 1980 flare area was observed at NSO-Sacramento Peak Observatory, simultaneously with the Universal Spectrograph and with the Universal Birefringent Filter in parallel with the Zeiss Hα filter. The authors consider the flare emission measured with the spectrograph in the Hβ, Hγ, Hδ, Ca II-K and Na-D2 lines to detect possible asymmetry in their profiles. A characteristic blue asymmetry, indicative of coronal upflows, is present in the Ca XIX spectrum obtained with the Bent Crystal Spectrometer on the Solar Maximum Mission. This is qualitatively consistent with the generally accepted scenario of a chromophseric evaporation sufficiently rapid to drive both coronal upflows and chromospheric downflows. The velocities obtained from chromospheric lines are compared with the ones predicted by numerical simulations of gas dynamics in flare loops (Fisher 1986, 1989). The results show that the chromospheric condensation, predicted to be moving downwards with constant velocity within the condensation, probably has a velocity gradient and that the layers ahead of it seem to be affected by the motion of the condensation. Title: Velocity Field in the 1980JUN13 Flare Area Authors: Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1992LNP...399..342F Altcode: 1992esf..coll..342F; 1992IAUCo.133..342F No abstract at ADS Title: Narrow Bandpass Filter Solar Observations Authors: Smaldone, L. A.; Cauzzi, G.; Keil, S. L. Bibcode: 1991BAAS...23.1057S Altcode: No abstract at ADS Title: High resolution spectropolarimetry of an active region. Authors: Bonaccini, D.; Landi Degl'Innocenti, E.; Smaldone, L. A.; Tamblyn, P. Bibcode: 1991sopo.work..251B Altcode: Some spectropolarimetric observations at moderately high spatial resolution are presented. The observations, obtained through a Fabry-Perot interferometer in cascade of an Universal Birefringent Filter, show the high potentiality of this spectroscopic technique for the detailed analysis of solar active regions. Title: Needs and constraints for coordinated programs of photospheric and chromospheric studies of flares Authors: Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1991AdSpR..11e..85F Altcode: 1991AdSpR..11...85F Suggestions for a coordinated observing program of the photospheric and chromospheric components of a flare are given; the maximum efficiency can be reached only if simultaneous measurements of coronal emission component may be obtained. The observing program has to be changed according to the different characteristics of a flare in each phase of its development. During the build-up phase it is of particular interest to establish the correlation between the photospheric velocity field (determined from bidimensional spectroscopic images in the 5576 Fe I line) and the magnetic field. During the transient explosive phase particular emphasys should be given to high time resolution observations (at least 1 sec) in order to correlate the response of chromospheric and photospheric signatures to the energy release producing the impusive phase in the hard X-ray and microwave emission. Observations with different filters in the center and red wing of the Hα line, in CN (0-0) band and in some continuous windows are suggested in order to have time and spatial resolution as high as possible. Spectral observations in the region 3400 - 4300 Å give the possibility to measure the red shift of the Balmer lines presumably associated to the chromospheric condensation moving downward. When the flare atmosphere may be considered in pressure balance (after tens of seconds) the time resolution is not crucial and the Hα and Na-D2 line profile may be obtained with the Zeiss and UBF filter used in bidimensional spectroscopic mode. Hα line gives the possibility to test the effect of the heating mechanism while the Na-D2 line is useful to monitor the penetration depth of the flare disturbance. Title: Analysis of the optical spectra of solar flares. V - Sensitivity of the hydrogen Balmer signatures and of the Na-D2 line profile to different energy transport mechanisms Authors: Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1990A&AS...84..601F Altcode: The effects of nonthermal electron flux, thermal conductive flux, and coronal pressure on the behavior of spectral signatures are investigated using various solar flare models. The method used to derive the Balmer and Na-D2 is described. It is observed that: a high value for the nonthermal electron flux is indicated by very broad wings of the Balmer lines and a well developed pseudocontinuum emission; a central emission reversal depicts a small coronal pressure value; and an intense Balmer line combined with a very weak Balmer continuum indicate a high coronal pressure value, but a low electron flux value. Changes in the Na-D2 line are detected only in the core of its profile. It is also detected that an increase in the conductive flux over a threshold level decreases both lines, the Balmer continuum, and the Na-D2 line core emission. Title: Two-Dimensional High-Resolution Spectroscopy of Quiet Regions on the Sun Authors: Bonaccini, D.; Cauzzi, G.; Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1990Ap&SS.170..117B Altcode: We present preliminary results of solar bi-dimensional spectroscopy observations obtained with the new 20 mÅ NSO-Sacramento Peak tunable filter. The procedures of image destretching and the corrections for the modulation of the 5-min oscillations are briefly discussed. Title: Anisotropies in solar oscillations Authors: Caccin, B.; Fofi, M.; Torelli, M.; Smaldone, L. A. Bibcode: 1990A&A...232..516C Altcode: Spherical harmonic filtering 20 less than or equal to l = m less than or equal to 100 has been applied to analyze a time series of Doppler observations in Na light in order to find eventual anisotropies between sectorial modes propagating along east-west and north-south directions. The results obtained show that the strongest power is connected with the north-south direction and that the power ratio NS/EW grows linearly with l. Title: Spectroscopic Observations of the dMe Flare Stars V1216 Sgr and V 1054 Oph Authors: Falchi, A.; Tozzi, G. P.; Falciani, F.; Smaldone, L. A. Bibcode: 1990ApL&C..28...15F Altcode: 1990ApL....28...15F No abstract at ADS Title: Did an outburst occur on 4 December 1985 in Halley's comet? Authors: Festou, M. C.; Tozzi, G. P.; Smaldone, L. A.; Felenbok, P.; Falciani, R.; Zucconi, J. -M. Bibcode: 1990A&A...227..609F Altcode: Two sets of complementary observations of large-amplitude brightness and gas production rate variations on Comet Halley made on 4.2-4.9 December, 1985 by two very different techniques are interpreted here using the atmospheric model of Festou (1981). The brightness observations are found to be not consistent with production of parent molecules at a steady rate. It is shown that a noticeable gas production increase occurred shortly before the observations were made. The interpretation of the OH line profile requires that the velocity of the parent molecules be larger than 1 km/s. A possible explanation in terms of a variable velocity of the H2O molecules is given. Title: Bi-dimensional solar spectroscopy with the 20 mÅ filter: capabilities and constraints. Authors: Cauzzi, Gianna; Smaldone, Luigi A. Bibcode: 1990SPIE.1318..193C Altcode: A new technique to perform bi-dimensional solar spectroscopy, by means of a narrow passband filter, is examined. The technique, combining high spatial and spectral resolution observations, allows the determination of the dynamic and thermodynamic parameters of the observed solar features, their spatial relationships and their evolution properties. The authors discuss this technique, its observational constraints and the data reduction procedures. Title: Some remarks on the data analysis problems in solar two-dimensional spectroscopy Authors: Cauzzi, G.; Smaldone, L. A.; Bonaccini, D.; Falciani, R. Bibcode: 1989hsrs.conf..261C Altcode: No abstract at ADS Title: Flare model sensitivity of the Balmer spectrum Authors: Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1989dots.work..183F Altcode: Careful studies of various chromospheric spectral signatures are very important in order to explore their possible sensitivity to the modifications of the thermodynamic quantities produced by the flare occurrence. Pioneer work of Canfield and co-workers have shown how the H alpha behavior is able to indicate different changes in the atmospheric parameters structure associated to the flare event. It was decided to study the behavior of the highest Balmer lines and of the Balmer continuum in different solar flare model atmospheres. These spectral features, originating in the deep photosphere in a quiet area, may have a sensitivity different from H alpha to the modification of a flare atmosphere. The details of the method used to compute the Stark profile of the higher Balmer line (n is greater than or equal to 6) and their merging were extensively given elsewhere (Donati-Falchi et al., 1985; Falchi et al., 1989). The models used were developed by Ricchiazzi in his thesis (1982) evaluating the chromospheric response to both the nonthermal electron flux, for energy greater than 20 kev, (F20) and to the thermal conduction, (Fc). The effect of the coronal pressure values (PO) at the apex of the flare loop is also included. Title: The evaluation of the Balmer merging effects in different chromospheric solar flare models. Authors: Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1989sasf.confP.345F Altcode: 1988sasf.conf..345F; 1989IAUCo.104P.345F Synthetic spectra computed with semiempirical and theoretical models of the flare atmosphere are discussed. Stark profile of the Balmer lines (n ≥ 6) and the Balmer continuum have been computed according to Donati-Falchi et al., (1985). A semiempirical model in between the F2 and F3 models proposed by Avrett et al., (1986) might represent a good approximation of the atmosphere of a flare during the impulsive phase. Among the theoretical models proposed by Ricchiazzi (1982), the model, indicated as 1073, with very high coronal pressure (Pυ = 1000 dyne cm-2) probably represents the best approximation of the emission observed during the impulsive phase of a chromospheric flare. Title: Balmer lines and continuum emission for two flares of the dMe star Gliese 729. Authors: Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1989sasf.confP..79F Altcode: 1989IAUCo.104P..79F; 1988sasf.conf...79F It has been shown for solar flares (Donati-Falchi et al., 1985) that the continuum emission at the Balmer discontinuity (the blue "pseudo-continuum") is a very sensitive tool to determine the electron density. In order to use the same interpretative scheme for stellar flares (Falchi et al., 1988), spectroscopic observations of various flare stars have been performed in June 1987 at ESO Observatory (Chile). In this paper the authors report the analysis of spectra of the star n. 729 (V1216 Sgr) of the Gliese catalog. Title: Bidimensional spectroscopy of network bright points Authors: Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1988SoPh..114...29F Altcode: We develop an automatic, computer controlled procedure to select and to analyze the Network Bright Points (NBPs) on solar images. These have been obtained at the Sac Peak Vacuum Tower Telescope by means of the Universal Birefringent Filter and Zeiss Hα filters, tuned, respectively, along the profiles of the Hβ, Mg-b1, Na-D2, and Hα lines. Title: JOSO Working Group 3 - Italian Contribution to a Data Analysis Package for Solar Physics Authors: Smaldone, L. A.; Tozzi, G. P. Bibcode: 1988iaia.conf...31S Altcode: No abstract at ADS Title: Observational Maps of the Moments of Strong Line Profiles on the Solar Disk Authors: Caccin, B.; Donati-Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1987SoPh..112..383C Altcode: Using the method of solar bidimensional spectroscopy based on the Universal Birefringent Filter (UBF), we have determined the bidimensional maps of moments of some chromospheric lines. The observational material, referring to a quiet region on the disk center, have been acquired with the UBF of the NSO at Sacramento Peak on Aug. 27,1985. In this note we present the work in progress and the new observational aspects arising from this diagnostic method. Title: Bidimensional spectroscopy of network bright points. I - Morphological properties Authors: Falchi, A.; Falciani, R.; Tozzi, G. P.; Smaldone, L. A. Bibcode: 1987SoPh..114...29F Altcode: An automatic computer-controlled method for the selection and analysis of network bright points (NBPs) on solar images is proposed which uses a universal birefringent filter (monitoring the H-beta, Mg-b1, and Na-D2 lines) and a H-alpha Zeiss Filter (monitoring the H-alpha line). Identification constraints are discussed, and various parameters, including position, area, mean and maximum contrast, Dopplergram velocity, and compactness, are measured for each NBP. Two types of NBPs are identified, the more frequently occurring type Is (found on the boundaries of the supergranular network) and the type IIs (preferentially found in the neighborhood of small, compact sunspots). Title: Spatial distribution of neutral and ionized gas in the Halley comet coma after the perihelion. Authors: Falciani, R.; Festou, M.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1987PAICz..67...79F Altcode: 1987eram....2...79F Long slit Halley comet spectra taken at ESO Observatory after the perihelion have been analyzed. It has been shown that the comet increased its gas production rate of a factor 3 on 22.9 March 1986, then it decreased to half the 23.1 March 1986. Title: Spatial Asymmetries of Some Gas Emissions in the Head of Halley's Comet Authors: Falciani, R.; Festou, M.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1986ESASP.250c..75F Altcode: 1986ehc3.conf...75F Long slit visible spectra of Halley comet were recorded on Oct. 18.98 - 19.23, Nov. 14.86 - 15.09 and Dec. 4.74 - 4.91, 1985, along the sunward direction. The radial profiles of the absolute intensity emitted by the most prominent visible gas bands (CN, C2, C3, NH2) have been obtained after careful reduction and elaboration of the spectra. These data have been interpreted using the vectorial model. On Dec. 4, it was possible to explain the measured radial profiles with the occurrence of two outbursts: the first one starting 1.5 days before the observations with an increase of the gas production rate of about an order of magnitude, the second one starting 0.6 days before, with an increasing of about 20% of the actual production rate. Title: Optical spectroscopy of the coma of comet Halley at ESO. Authors: Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1986Msngr..44...15F Altcode: Using optical spectra (3550-6800 A) obtained with the 1.5-m University of Bologna telescope for the preperihelion phase, and with the 1.52-m ESO telescope for the postperihelion phase, the coma of Comet Halley is studied. A total of 25 spectra were obtained with different slit orientations and exposure times. The observed extension of the scattered solar radiation implies a very extended dust component. Title: Interpretation of continuum emissions in white light flares. Authors: Falchi, A. Donati; Falciani, R.; Smaldone, L. A. Bibcode: 1986lasf.conf..136F Altcode: 1986lasf.symp..136F; 1986lasf.conf..136D The authors computed the spectrum emitted by a white light flare (WLF) schematically represented by an isothermal and uniform hydrogen slab of geometrical thickness h. They assumed, as continuum opacities, H-, Hb-f and Hf-f and included the effect of the merging of the Stark broadened profiles of the highest Balmer lines. They conclude that the interpretation of WLF spectra based only on very few "continuum" windows can be misleading. When feasible the analysis of the Balmer line profiles have to be properly taken into account, because these lines yield useful information to put efficient constraints on the set of physical parameters capable to explain the observed continuum emission. Title: Bidimensional spectroscopy observations of the 13 June 1980 flare. Authors: Donati-Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1986lasf.conf...59D Altcode: 1986lasf.symp...59D For two bright chromospheric kernels the authors determined a penetration depth of the flare disturbance of the order of 500 km above r0 = 1.0 and Te = 7000K. The brighter kernel seems to fit an uniform slab model with Ne = 1013cm-3 and geometrical thickness h = 150 km, the weaker one with Ne ≤ 6×1012cm-3 and h ≤ 10 km. The brighter kernel shows a downward motion of 12 km/sec at the time of the maximum development of the flare and seems to be connected with a weaker kernel (visible in Na-D2 and showing also a downward motion of 11 km/sec) by means of an absorbing loop (visible in He-D3). Three interacting chromospheric loops are detected as absorbing structures in He-D3. Title: Analysis of the optical spectra of solar flares. IV - The 'blue' continuum of white light flares Authors: Donati-Falchi, A.; Falciani, R.; Smaldone, L. A. Bibcode: 1985A&A...152..165D Altcode: The "blue" continuum emission at λ < 4000 Å of white light flares (WLF) has been interpreted as mainly due to the merging of the Stark broadened profiles of the highest Balmer lines. Stark profiles have been computed according to the deFeiter (1966) method, using the Griem (1962) asymptotic expressions for the electron broadening parameter. A homogeneous and isothermal model for the WLF has been used to compute a grid of emitted spectra; the NLTE hydrogen level populations are from deFeiter (1966). A satisfactory agreement between some computed spectra and those measured for the June 4, 1980 WLF has been found. Title: Spatial and Spectral Distribution of Photospheric Bright Points Authors: Donati-Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1985tphr.conf...91D Altcode: No abstract at ADS Title: Spatial and spectral distribution of photospheric bright points. Authors: Donati-Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P. Bibcode: 1985MPARp.212...91D Altcode: Spatial and spectral properties of isolated bright points (IBP) are studied. The authors conclude that the present IBP's properties can be produced by seeing effects on effective facular point characteristics. Title: Line Profiles and Longitudinal Velocity Field in Seeing Limited Small-Scale Atmospheric Structures Authors: Falchi, F.; Falciani, R.; Smaldone, L. A. Bibcode: 1985LNP...233..172F Altcode: 1985hrsp.proc..172F No abstract at ADS Title: Analysis of solar flares optical spectra. III - The line emission of the June 4, 1980 white light flare Authors: Donati-Falchi, A.; Sambuco, A. M.; Smaldone, L. A.; Falciani, R. Bibcode: 1984A&AS...55..425D Altcode: The spectra of the white light flare of June 4, 1980 observed with the Universal Spectrograph of the Sacramento Peak Observatory have been presented in paper II of this series. The authors give here all the parameters (central peak wavelength and intensity, width at half maximum, total power radiated in the line and so on) obtained from the line emission analysis for central part of the flare kernel. Title: Analysis of the optical spectra of solar flares. II - The energetics of the June 4, 1980 white light flare Authors: Donati-Falchi, A.; Smaldone, L. A.; Falciani, R. Bibcode: 1984A&A...131..256D Altcode: The spectra of the white light flare of June 4, 1980 observed with the Universal spectrograph at the Sacramento Peak Observatory, have been carefully analyzed with the interactive reduction procedure referred to in Paper I of this series. The spectra of the flare kernel (possibly the real footpoint of the flaring magnetic loop) have been divided into 6 different adjacent strips in order to determine the variation of emissions within the kernel itself. The authors obtain the absolute values of the continuum and line emission. The time evolution of the energy radiated in the optical range by the flare is also obtained and the total energy in the range 3600 - 5900 Å is estimated to be 1.35×1030erg between 225950 UT and 230447 UT. Title: Bidimensional spectroscopy of the solar chromosphere during the maximum year Authors: Caccin, B.; Falchi, A.; Falciani, R.; Roberti, G.; Smaldone, L. A. Bibcode: 1984AdSpR...4g.215C Altcode: 1984AdSpR...4..215C Our program was based on simultaneous observations of the same solar region with the Universal Birefringent Filter (UBF) at the Vacuum Tower Telescope (VTT) and with the Big Dome BD Universal Spectrograph (USG). For the UBF images analysis we refer to the 13 June 1980 RG 2502/2511 (N12-E11) observations. Selected pictures present the line profiles for Hα, Hβ, Mg-b1 and Na-D2 at some interesting ``pixels'' of the analyzed AR. We present the detailed photometric morphology of the observed active area and the longitudinal velocity field pattern. A comparison with the corresponding UVSP data is given. Title: Recommendations on post focus instrumentation for LEST. Authors: Wöhl, H.; Huber, M. C. E.; Mein, P.; Smaldone, L. Bibcode: 1984LFTR....5.....W Altcode: No abstract at ADS Title: Bidimensional Analysis of Solar Active Regions and Flares - Part One - Imaging Spectroscopy with Universal Birefringent Filters Authors: Caccin, B.; Falciani, R.; Roberti, G.; Sambuco, A. M.; Smaldone, L. A. Bibcode: 1983SoPh...89..323C Altcode: We describe a method of solar bidimensional spectroscopy exploiting the performances of a Universal Birefringent Filter (UBF) like that of the Sacramento Peak Observatory, which enable an estimate of the profile of some chromospheric lines with moderate spectral resolution (). The numerical inversion technique of Backus and Gilbert has been used to retrieve the estimated line profiles; the capabilities of the proposed method is fully analyzed with some numerical tests and examples. Correction procedures for errors in the positions of the UBF passband, random fluctuations of the exposure times and non-uniform brightness distribution on the filtergrams are also presented. The whole method has been tested on the recovery of quiet atmosphere line profiles and the results derived for the Na D2 line show that the proposed method is completely suitable for many investigations in solar physics. Title: Analysis of the optical spectra of solar flares. I - The flare of April 30, 1976 Authors: Acampa, E.; Smaldone, L. A.; Sambuco, A. M.; Falciani, R. Bibcode: 1982A&AS...47..485A Altcode: A novel interactive method for the reduction of solar flare spectra is described which permits the determination of values in the continuum emission of the flare, as well as such line emission parameters as wavelength, line maximum emission intensity, halfwidth, total emissivity within the line, and line identification. The procedure has been tested on existing observational material, and results are presented for the case of the April 30, 1976 flare spectra. Title: Digital processing of high resolution solar filtergrams. Authors: Caccin, B.; Russo, P.; Smaldone, L. A. Bibcode: 1982MmSAI..53..287C Altcode: The authors describe the techniques for digital processing of high resolution solar filtergrams developed at the Naples ASTRONET station. Preliminary results obtained with Hα filtergrams provided by the Ottawa River Solar Observatory are presented. Title: Magnetic Fine-Structures and Granular Velocities Authors: Caccin, B.; Falciani, R.; Gomez, M. T.; Marmolino, C.; Roberti, G.; Severino, G.; Smaldone, L. A. Bibcode: 1981SSRv...29..373C Altcode: In the last years we have gained some experience in the diagnostics of small-scale structures, both on the interpretative and on the observational point of view. We report here the conclusions and the suggestions for future developments attained in two main fields of interest. Title: Some Results Concerning the Automatic Photometry of Photographic Chromospheric Images Authors: Azzarelli, L.; Casalini, P. L.; Cerri, S.; Falciani, R.; Roberti, G.; Smaldone, L. A. Bibcode: 1981SoPh...71..247A Altcode: The results of an exploratory work on the use of a high-speed, computer-controlled flying-spot for quantitative photometry of solar Hα images are given. The used method is briefly illustrated and applied to the study of the photometric structure and evolution of some chromospheric active regions. Evolutive curves and isophotes for the 27 October 1969 plages (McMath 10381 and 10385) are presented. Title: Interactive reduction of solar flare spectra Authors: Acampa, E.; Falciani, R.; Sambuco, A. M.; Smaldone, L. A. Bibcode: 1980MmSAI..51..423A Altcode: No abstract at ADS Title: Far infrared spectroscopy during ESA/NASA ASSESS II mission Authors: Melchiorri, B.; Melchiorri, F.; Natale, V.; Falciani, R.; Smaldone, L. A.; Bussoletti, E. Bibcode: 1978MmSAI..49...43M Altcode: One of the seven experiments selected by ESA for the NASA/ESA ASSESS II (Airborne Scientific Spacelab Experiment System Simulation, II) mission is described. The objectives of this experiment include measurements of the temperature distribution in the upper solar atmosphere, IR emission and absorption in the upper atmosphere of earth, and the limit of anisotropy in sky emission. The equipment used for these measurements is discussed, and a rough ground-calibration spectrum is presented to illustrate the performance of the equipment. It is noted that about 40 interferograms of the sun, more than 100 interferograms of terrestrial atmospheric emission, and some 10 hr of data on sky-noise anisotropy have been obtained to date. Title: Far infrared spectroscopy during ESA/NASA ASSESS II mission. Authors: Melchiorri, B.; Melchiorri, F.; Natale, V.; Falciani, R.; Smaldone, L. A.; Bussoletti, E. Bibcode: 1978ASIC...38...43M Altcode: No abstract at ADS