Author name code: kovacs ADS astronomy entries on 2022-09-14 author:"Kovacs, Agnes" year:1960-1999 -aff:"Cambridge" -aff:"Pasadena" ------------------------------------------------------------------------ Title: Design of the Gemini near-infrared spectrometer Authors: Elias, Jonathan H.; Vukobratovich, Daniel; Andrew, John R.; Cho, Myung K.; Cuberly, Randy W.; Don, Ken; Gerzoff, Allen; Harmer, Charles F.; Harris, D.; Heynssens, Julie B.; Hicks, J.; Kovacs, A.; Li, Cheng; Liang, M.; Moon, Il K.; Pearson, Earl T.; Plum, G.; Roddier, Nicolas A.; Tvedt, J.; Wolff, Richard J.; Wong, Woon-Yin Bibcode: 1998SPIE.3354..555E Altcode: The design of a near-IR spectrometer for the Gemini 8m telescopes is described. This instrument, GNIRS, provides coverage from 0.9 to 5.5 micrometers at several spectral resolutions and two pixel scales. Capabilities include an imaging mode intended primarily for acquisition, a cross- dispersed mode covering wavelengths from 0.9 to 2.5 micrometers , and provisions for an integral field unit. The design of the GNIRS is conservative, as it must meet tight schedule and resource constraints; it nonetheless provides high throughput and operational efficiency, minimal flexure, and the flexibility needed to support queue observing. The optics are a combination of diamond-turned metal optics for the fore-optics and collimator, and refractive optics for the cameras. The mechanism include a two-axis grating turret; all mechanism are deposited by means of internal detents. The instrument achieves low flexure within its weight budget by the use of a modular structure composed of cylindrical light-weighted sections into which individual mechanisms and optics modules are mounted. Extensive analyses of mechanical and optical performance have been performed. The GNIRS has passed its critical design review, and fabrication is now underway. Title: Sunspot motion and flare occurrences Authors: Dezsö, L.; Kovács, Á. Bibcode: 1998PAICz..88...17D Altcode: No abstract at ADS Title: Formation of a Solar Filament Channel Authors: Gaizauskas, V.; Zirker, J. B.; Sweetland, C.; Kovacs, A. Bibcode: 1997ApJ...479..448G Altcode: We present observations of the early stages of formation of a filament channel when a compact activity complex emerged in a previously quiet, near-equatorial area. In a few hours, and while flux was rising rapidly in one bipolar component in the complex, H alpha fine structure overlying a polarity inversion zone organized into a conspicuous pattern of parallel fibrils enclosing the trailing end of the new activity complex. Yet it took another 4 days for a stable filament to form inside that pattern. It did so at a place where migrating positive polarity flux from the new activity complex contacted the negative polarity flux in a plage of an adjacent decaying bipolar active region. In contrast, no filament formed along an existing channel inside the adjacent decaying region; the opposite-polarity fluxes on the borders of the existing channel showed no signs of convergence. We attribute the fibril-aligning forces in the new channel to the horizontal component of an extended nonpotential magnetic field caused by currents in the multipolar activity complex. The channel is, in this view, an elementary part of the magnetic topology of an activity complex. We propose that the later formation of the filament in the new channel requires an additional and separate process. A plausible candidate for this second step is the development of a current sheet at the site of converging magnetic flux. Title: Detection and Characterization of the Cumulene Carbenes H2C5 and H2C6. Authors: McCarthy, M. C.; Travers, M. J.; Kovacs, A.; Chen, W.; Novick, S. E.; Gottlieb, C. A.; Thaddeus, P. Bibcode: 1997Sci...275..518M Altcode: No abstract at ADS Title: Sunspot Motion and Flare Occurrences Authors: Dezső, L.; Kovács, Á. Bibcode: 1997eaun.book....3D Altcode: No abstract at ADS Title: Laboratory detection of the C_8_H radical. Authors: McCarthy, M. C.; Travers, M. J.; Kovacs, A.; Gottlieb, C. A.; Thaddeus, P. Bibcode: 1996A&A...309L..31M Altcode: The C_8_H radical has been detected in an argon-acetylene discharge, conclusively confirming the identification by Cernicharo and Guelin in the accompanying Letter of their new linear molecule in IRC+10216. In addition to the ground ^2PI_3/2_ rotational ladder, the ^2PI_1/2_ ladder 19cm^-1^ above ground has been detected, and the entire fine structure-rotational spectrum calculated. The standard ^2PI Hamiltonian fits the laboratory measurements of more than 30 radio lines between 80 and 100GHz to high accuracy; yields precise values for the rotational, fine structure, and lambda-doubling constants; and allows the astronomically most interesting lines in the radio spectrum to be predicted to an uncertainty of 0.1km/s or better. Title: On the Differential Rotation of the Solar Photosphere Authors: Dezso, L.; Kovacs, Agnes Bibcode: 1994SoPh..151..385D Altcode: It is shown that sunspots as tracers can give the same results for the differential rotation of the solar photosphere as the Doppler-shift measurements, if the sunspots used have only insignificant motion relative to their immediate photospheric surroundings. Title: On the differential rotation of the solar photosphere. Authors: Dezsö, L.; Kovács, A. Bibcode: 1994soro.conf..136D Altcode: No abstract at ADS Title: An account of sunspot group developments on the basis of the `Debrecen Photoheliographic Results' Authors: Dezsö, L.; Kovács, Á. Bibcode: 1994smf..conf...55D Altcode: No abstract at ADS Title: An Analysis of Surges Triggered by a Small Flare Authors: Kovacs, Agnes; Dezso, L. Bibcode: 1990SoPh..129..313K Altcode: On 22 October, 1980, near the solar central meridian in the western vicinity of a large spot group, a subflare of the two-ribbon type was observed. Three surges were associated with this flare. Their starting points were situated close to the principal flare patches on both sides of a short filament that was visible for only a few hours. True flow velocities and decelerations along the arch-shaped surge trajectories have been determined for two of the surges. The highest velocities were found at the onset of the surges. Title: Problem of short-term prediction of solar flare activity. V - Spatial consistence between hard X-ray enhancement and strong X-ray appearance Authors: Jakimiec, M.; Kovacs, A. Bibcode: 1990AcA....40..305J Altcode: The aim of this paper is verification of the suggestion that small faint flares with enhanced harder X-ray flux may be precursors of strong flare activity and, as precursors, they should be located in the sunspot group where strong X-ray flares occur. Statistical analysis is based on the observations obtained at Debrecen Heliophysical Observatory and also on the standard flare observations given in Solar Geophysical Data. The analysis proved that the hypothesis of random location over the area of the sunspot group of both precursors and the other faint flares should be rejected. Consequently, it may be said that, before strong flares, the precursors appear more often in their vicinity than the other faint flares do. Title: An Analysis of Surges Triggered by a Small Flare Authors: Kovács, Agnes; Dezsõ, L. Bibcode: 1990LNP...363..261K Altcode: 1990IAUCo.117..261K; 1990doqp.coll..261K On 22 October 1980, near the solar central meridian, in the western vicinity of the large spot group, a subflare of the two-ribbon type was observed. Three surges were associated with this flare. Their starting points were situated close to the principal flare patches on both sides of a short filament that was visible for only a few hours. True flow velocities and decelerations along the arch-shaped surge trajectories have been determined for two of the surges. The event was studied from a series of Ha on- and off-band filter-grams taken through the Debrecen coronagraph of 53 cm aperture. Title: Photoheliographic results for the year 1977. Authors: Dezsö, L.; Gerlei, O.; Kovács, Á. Bibcode: 1987PDHO....1...11D Altcode: The paper contains the results of measurements of positions and areas of sunspots observed during the year 1977. Title: Development of sunspot groups related to the solar differential rotation during the early period of a new solar cycle. Authors: Dezso, L.; Kovacs, A. Bibcode: 1987PAICz..66...81D Altcode: 1987eram....1...81D Diverse spot distributions and the principal spot motions within the groups, as well as the local solar rotation in several regions of spot groups by means of tracers of spot positions have been determined. The most important characteristics found are presented. Title: A comparison between Greenwich and Debrecen measurements of sunspot positions. Authors: Kovács, Á. Bibcode: 1987PDHO....1..211K Altcode: No abstract at ADS Title: Sunspot motion as precedents of increasing flare activity Authors: Kovacs, Agnes; Dezso, L. Bibcode: 1986AdSpR...6f..29K Altcode: 1986AdSpR...6...29K Sunspot motion determined on the basis of white-light heliograms taken in Debrecen and Gyula, during FBS Actions and on other occasions, were compared with flare occurrence data. Several examples were found showing convincingly that magnetic shears caused by the relative motion of originally unconnected sunspot pairs of opposite polarity are often followed by some prominent flares and/or a substantial increase in flare activity for a period of one day or so. Title: An analysis of the relationship between X-ray and H-alpha flares Authors: Jakimiec, M.; Kovács, Á. Bibcode: 1986CoSka..15..671J Altcode: No abstract at ADS Title: Sunspot motion in Hale region No. 18430 Authors: Kovács, Á.; Dezsö, L. Bibcode: 1986CoSka..15..103K Altcode: On the basis of sunspot positions, measured on full-disc white-light heliograms, the spot motions of a new solar active region have been studied. All spots were followed from birth over their whole discpassage in the period of June 16 - 26, 1982. Within a few days a large sunspot group was fully developed that was associated with a number of major flare occurrences (two of them have been reported even as white-light flares). Title: On the quasi-homologous limb flares observed on 3 August 1981 Authors: Dezsö, L.; Fludra, A.; Gerlei, O.; Jakimiec, J.; Kovács, Á.; Pettauer, T. Bibcode: 1986AdSpR...6f..65D Altcode: 1986AdSpR...6...65D Five limb flares and a large surge, triggered obviously by the second flare, have been investigated on the basis of Hα on- and off-band heliograms and X-ray data obtained during a 6-hour period on 3 August 1981. In addition, in the vicinity of the flare location the sunspots and filaments were followed by observations over several of the former days too. Emphasis was layed on the ascending motion in the course of flare build-up and on the time evolution of the flare energy release using GOES observations in the case of the first and second flares. It was found that their ascending Hα flare kernels, which reached to a height of 20-25×103 km, have been the main center both the source and the starting points of flare loops and perhaps also the main site of the soft X-ray emissions. Title: Sunspot motions and magnetic shears as precusors of flares Authors: Dezso, L.; Csepura, G.; Gerlei, O.; Kovacs, A.; Nagy, I. Bibcode: 1984AdSpR...4g..57D Altcode: 1984AdSpR...4...57D Using full-disc white light photoheliograms, we have studied umbrae motion and variations in sunspot areas in a large activity complex over 4 solar rotations. On the basis of the observational data we illustrate with typical examples to what extent rapid spot motions are associated with flare occurrences. Title: A note on flare loops. Authors: Dezsö, L.; Kovács, Á. Bibcode: 1983PDHO....5..317D Altcode: 1984PDHO....5..317D It is shown that even the flash phase of a typical flare consists mainly of loops, when the bulk of energy release took place. Consequently the flare phenomenon may be regarded as a loop system temporarily in a highly excited state. Title: A Note on Sunspot Group Development SPOT Motions and Solar Rotation Authors: Dezso, L.; Kovacs, A. Bibcode: 1981PDHO....4...35D Altcode: No abstract at ADS Title: Motions in the solar atmosphere associated with the white light flare of 11 July 1978 Authors: Dezso, L.; Gesztelyi, L.; Kondas, L.; Kovacs, A.; Rostas, S. Bibcode: 1980SoPh...67..317D Altcode: Series of white light heliograms and oft- and on-band Hα filtergrams have been obtained, with an average spatial resolution of 1″, to study the flare active McMath region 15403 on 11 July, 1978. A great number of accurate heliographic positions were determined for the umbrae, the white light flare patches and several bright Hα flare knots, as well as along the principal zero filament and an arch prominence. Using the measured heliographic coordinates of these objects their motions could be analyzed in some detail. The velocities of several different objects could be deduced from the coordinates. Since the heliocentric angle of the region was about 45°, the variation in apparent heliographic coordinates also enabled some variations in heights to be determined. Title: The development of the sunspot group associated with the white light flare of July 1974. Authors: Kovács, Á. Bibcode: 1977PDHO....3..207K Altcode: No abstract at ADS Title: Results of a study of the active region McMath 13736 according to the cooperative KAPG program "The birth of active regions". Authors: Alikaeva, K. V.; Akhmedov, Sh. B.; Baranovskij, Eh. A.; Gel'Frejkh, G. B.; Dezsoe, L.; Gyertyanos, G.; Ioshpa, B. A.; Ishkov, V. N.; Kalman, B.; Kartashova, L. G.; Koval'Chuk, M. M.; Kovacs, A.; Laba, I. S.; Olijnyk, P. A.; Orudzhev, Eh. Sh.; Mamedov, S. G.; Rakhubovskij, A. S.; Seidov, A. G.; Sikora, J.; Stepanyan, N. N. Bibcode: 1976veao.conf...21A Altcode: No abstract at ADS Title: Proper motions of sunspot groups Nos. 50 and 52 of S.D., 1975. Authors: Dezsoe, L.; Gyertyanos, G.; Kalman, B.; Kovacs, A. Bibcode: 1976veao.conf...48D Altcode: No abstract at ADS Title: Investigations on the program "Rapid variations of solar magnetic fields", IV. Motions of sunspot umbrae. Authors: Dezsoë, L.; Gyertyáos, G.; Kálmán, B.; Kovács, A. Bibcode: 1971BSolD1971...77D Altcode: No abstract at ADS Title: The Migration of Sunspot Activity Along Solar Meridians and Parallels Authors: Dezsö, L.; Gerlei, O.; Kovács, Ágnes Bibcode: 1968IAUS...35...70D Altcode: No abstract at ADS Title: Das Flächenverhältnis von Penumbra zur Umbra in Sonnefleckengruppen Authors: Dezsö, L.; Kovács, A. Bibcode: 1965BAICz..16...76D Altcode: No abstract at ADS