Search Publications
Analysis of Selected Runaway Stars in the Orion Nebula Based on Data from the Gaia EDR3 Catalogue
Bobylev, V. V.; Bajkova, A. T.
We have performed Monte Carlo simulations of the trajectories of several runaway stars using their parallaxes and proper motions from the Gaia EDR3 catalogue. We have confirmed the hypothesis that the stars AE Aur and $µ$ Col are a product of the multiple system breakup ${∼}2.5$ Myr ago and the Orion Trapezium may be the parent cluster for t…
Study of the Influence of an Evolving Galactic Potential on the Orbital Properties of 152 Globular Clusters with Data from the Gaia EDR3 Catalogue
Bobylev, V. V.; Bajkova, A. T.; Smirnov, A. A.
We have studied the influence of an evolving gravitational potential of the Milky Way Galaxy on the orbital motion of 152 globular clusters with proper motions from the Gaia EDR3 catalogue and mean distances from Baumgardt and Vasiliev (2021). To construct a semicosmological evolving model potential with changing masses and sizes of the Galactic c…
Kinematic Properties of the GAIA EDR3 Catalogue
Tsvetkov, A. S.
We have obtained a solution of the Ogorodnikov-Milne stellar-kinematics equations based on the material of the entire Gaia EDR3 star catalogue containing 1.8 billion objects. In view of the insufficient accuracy of individual trigonometric parallaxes, we have also obtained an analogous solution based on a sub-catalogue of selected 98 million stars…
Changes in the Period of SU Sct, a Population II Cepheid
Berdnikov, L. N.; Pastukhova, E. N.
The reduction of all the available photometry for the Cepheid SU Sct has allowed its $O-C$ diagram spanning a time interval of 60 years to be constructed. Six abrupt changes in the period have been detected. The pulsation stability test proposed by Lombard and Koen (1993) has confirmed that the changes in the period are real. The absolute magnitud…
To the Globular Cluster Classification Problem. Calculating the Concentration of Stars for 26 Clusters
Nuritdinov, S. N.; Tatjibaev, I. U.; Rastorguev, A. S.
In view of the absence of a satisfactory solution to the globular cluster (GC) classification problem, we have searched for a physical parameter that admits of the GC classification and finding empirical dependences on observed physical characteristics. For this purpose, we have considered a model of the apparent density in GCs with three free par…
Spectroscopic Variability of the Compact Planetary Nebula Hb 12
Arkhipova, V. P.; Esipov, V. F.; Ikonnikova, N. P. +5 more
We present the results of our new low-resolution spectroscopic observations of the young compact planetary nebula Hb 12 performed in 2011-2020 with SAI MSU telescopes. We have measured the intensities of more than 50 nebular emission lines in the spectral range $λ$3687-9532, detected interstellar absorption features, and conducted a search for abs…
Changes in the Period of V420 Cen, a W Vir-Type Cepheid
Berdnikov, L. N.
The reduction of all the available photometry for the Cepheid V420 Cen has allowed its $O-C$ diagram spanning a time interval of 131 years to be constructed. The data obtained provide evidence for the existence of large random fluctuations in the period ($\varepsilon/P≈ 0.021$). Fitting the $O-C$ residuals by a cubic parabola has made it possible …
Search for Evolutionary Changes in the Periods of the Cepheids CEa Cas and CEb Cas
Berdnikov, L. N.; Pastukhova, E. N.; Ikonnikova, N. P. +4 more
For two classical Cepheids, CEa Cas and CEb Cas, members of the open cluster NGC 7790, we have constructed $O-C$ diagrams spanning a time interval of 125 years. The $O-C$ diagrams have the shape of parabolas, which has allowed us for the first time to determine the quadratic light elements and to calculate the rates of evolutionary changes in thei…
Search for Magnetars in the Galaxy M31 as Periodic X-ray Sources Based on XMM-Newton Data
Popov, S. B.; Pshirkov, M. S.; Zolotukhin, I. Yu.
Several years ago a series of powerful millisecond radio bursts with close dispersion measures was detected toward the galaxy M31. Taking the hypothesis about the possible association of these radio bursts with a magnetar in M31 as a starting point, we have searched for periodic X-ray signal sources using data from the XMM-Newton X-ray telescope. …
Multicolor Photometry and Peculiarities of the Spectrum for the post-AGB Candidate AU Vulpeculae (IRAS 20160+2734)
Esipov, V. F.; Ikonnikova, N. P.; Tatarnikov, A. M. +7 more
We present the results of a UBVRcIc and JHKLM photometric monitoring campaign conducted in 2016-2020, low-resolution spectroscopy, and an analysis of the ASAS-3 and ASAS-SN photometric data for the semiregular variable and post-AGB candidate AU Vul (IRAS 20160+2734). The star is shown to experience quasi-periodic brightness oscillations with a var…