Search Publications
Multiwavelength studies of X-ray selected extragalactic sample.
Mickaelian, A. M.; Abrahamyan, H. V.; Paronyan, G. M. +2 more
The joint catalogue of Active Galactic Nuclei selected from optical identifications of X-ray sources was created as a combination of two samples: Hamburg-ROSAT Catalogue (HRC) and Byurakan-Hamburg-ROSAT Catalogue (BHRC). Both are based on optical identifications of X-ray sources from ROSAT catalogues using low-dispersion spectra of Hamburg Quasar …
The nature of X-ray selected star candidates
Gigoyan, K. S.; Kostandyan, G. R.; Mickaelian, A. M. +3 more
The joint HRC/BHRC catalogue of optical identifications of ROSAT BSC and FSC X-ray sources is based on merging the Hamburg-ROSAT Catalogue (HRC) and Byurakan-Hamburg-ROSAT Catalogue (BHRC). Both have been made by optical identifications of X-ray sources based on low-dispersion spectra of the Hamburg QuasarSurvey (HQS) using the ROSAT Catalogues. H…
Mass determination for visual binaries
Cvetković, Z.; Ninković, S.
We consider a sample of 432 visual binaries having orbital elements and belonging to the Main Sequence. We calculate their total masses using the orbital elements and the new Hipparcos parallaxes by applying Kepler's third law. For the same pairs the total masses are also found by applying the mass-luminosity relation. The source for the apparent …
Three methods to identify local Galactic structures
Cubarsi, R.; Alcobé, S.; Vidojević, S. +1 more
Method one: by combining a sampling parameter related to an isolating integral of the stellar motion, an optimisation of the mixture approach, and a maximisation of the partition entropy for the constituent populations of the stellar sample. Method two: by segregating into different kinematical components in terms of the stellar orbital parameters…
Autocorrelation analysis of the Crimean and Hipparcos photometry of the runaway star HD 188001
Barannikov, A. A.
Crimean photoelectric photometry and Hipparcos epoch photometry of runaway star HD 188001 are presented. Data processing of this observation by a form of autocorrelation analysis confirms the periodic (P = 32.514~d) variability of this star.
Modelling of light and radial velocity curves in close binary systems: masses of stars and relativistic objects
Antokhina, E. A.
Synthesis methods for close binary systems allow the fundamental parameters of stars and relativistic objects to be reliably determined. The masses of massive hot stars and relativistic objects are of special interest in order to test stellar evolution theories. We present the results of light curve analysis, which allows us to determine stellar m…
Radial velocities of 35495 Hipparcos stars in a common system
Gontcharov, G. A.
The Pulkovo Compilation of Radial Velocities (PCRV) catalogue has been produced to study stellar kinematics in the local spiral arm. The PCRV contains the mean weighted absolute radial velocities of 35495 Hipparcos stars of various spectral types and luminosity classes over the whole celestial sphere mainly within the radius of 500pc from the Sun.…
The rotational vector of the Local Stellar System
Tsvetkov, A. S.
It is shown that the rotational vector of nearby stars derived from the proper motions of the Hipparcos catalogue is not perpendicular to the Galactic plane. We found that the rotation of stars nearer than 150 pc can be considered as the superposition of the Galactic rotation and the Local Stellar System rotation. The kinematics of stars which are…
Search for the periodicity in brightness and radial velocity variations of the runaway star HD 218915
Barannikov, A. A.
An analysis of the variations in the brightness and radial velocity of the high-velocity (runaway) star HD 218915 based on the author's ground-based Crimean observations and from Hipparcos data is presented. The analysis leads to the conclusion that there is a periodic component in the brightness and radial velocity variations of HD 218915. The pe…
Autocorrelation and Fourier analysis of the Crimean and Hipparcos photometry of the runaway star HD 192281
Barannikov, A. A.
New B sbnd V sbnd R photoelectric photometry of the runaway star HD 192281 combined with Hipparcos observations of this star show a periodic brightness variation with a period of 67.385 days.