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Spectrophotometry of nine stars with planets
Tereschenko, V. M.
The energy distributions in the spectra of nine stars with planets were obtained from observations. The synthetic colour indices in the photometric UBV, WBVR and the Tycho catalogue systems were calculated on the basis of observations. The effective temperatures and metallicities of the investigated stars were determined by comparing the calculate…
Proper motions of open star clusters from Tycho-2 catalogue data
Beshenov, G. V.; Loktin, A. V.
The results of determinating the proper motions of open clusters on the basis of the Tycho-2 catalogue data are presented here. The resulting catalogue contains mean proper motions for 390 open clusters.
On putting the catalogues of the relative proper motions of open cluster stars in one system (cluster M67)
Loktin, A. V.
In this paper a method for putting the catalogues of the proper motions of cluster stars in one system is discussed on the base of numerical experiments. The catalogue of proper motions of stars in the field of open cluster M67 based on five catalogues of relative proper motions and the Tycho-2 catalogue is compiled.
Contribution of HIPPARCOS to the Determination of Precession
Vityazev, V. V.
The IAU (1976) luni-solar precession constant was derived by Fricke from intensive study of the catalog of 512 FK4-FK4/Sup distant stars. At present, when the data from the catalog HIPPARCOS is available, it is helpful to reconsider Fricke's analysis. This paper presents a redetermination of precession based on the following new factors: (a) the a…
Effective Temperatures of Solar Type Stars
Shenavrin, V. I.; Glushneva, I. N.; Roshchina, I. A.
For 29 stars of G0-G5 spectral types with color indices 0.60 leq Bndash V le 0.68 and parallaxes obtained by Hipparcos satellite effective temperatures, angular diameters and radii are determined by means of the method of infrared fluxes (IRFM) on the basis of JHKLM photometry. Effective temperatures obtained by iterations in the process of combin…
Solar large-scale emitting chains: Preliminary remarks on the cycle variability
Chertok, I. M.
Preliminary remarks on the solar cycle phase variability of the microwave and EUV large-scale chains are outlined briefly based on the Nobeyama Radioheliograph and SOHO/EIT data. The observed complication of the chains in the course of the cycle appears to reflect the corresponding complication of the global solar magnetosphere.
Timing of gamma-ray pulsars: Search in seven-parametric space
Bisnovatyi-Kogan, G. S.; Repin, S. V.
Timing of the Geminga gamma-ray pulsar is done using the data of COS B and EGRET. It is shown, that errors in angular coordinates of sources similar to Geminga strongly influence the determination of , so that at angular precision less then 10^-3 arc sec determination of the value of by means of this criterion gives an error of more than 100%. Att…
Formation of resonance spectral line profiles in stellar wind: Theory and observations
Sapar, L.; Sapar, A.
The theory of the formation of resonance spectral line profiles in the stellar wind of hot stars has been elaborated taking into account the presence of microturbulent motions. In this case the local frequency redistribution in the line profile function is incomplete. This circumstance generates dominating backscattering of photons and drastic cha…
The corona and the solar wind as a manifestation of the solar high speed mass emanation.
Nikolskaya, K. I.; Valchuk, T. E.
A concept of the solar corona and the solar wind resulting from the interaction between the solar primary high speed mass emanation and over-photospheric magnetic fields is outlined and developed. The model arises from the recent view of the solar corona spatial structure and Ulysses solar wind measurement data. The initial solar fast outflow is f…
New Insights on Late-A and Early-F Star Activity
Talavera, A.; Freire Ferrero, R.; Bruhweiler, F. +3 more
The onset of chromospheric activity in late-A and early-F stars is here discussed. The detection of Ly- emission core in several A and F atars with the IUE satellite, gives evidence for the presence of chromospheric layers in these stars up to B - V = 0m.19 (Marilli et al., 1996). Semiempirical chromospheric models for Altair allowed us (Freire Fe…