Destruction of Galaxies as a Cause of the Appearance of Stellar Streams

Astronomy Reports - The interaction of galaxies in clusters with the intergalactic gaseous medium and other galaxies is considered. The causes for the appearance of gaseous and stellar...     

Circumsolar Stellar Streams and Meteors in the Earth Atmosphere

Astronomy Reports - On the basis of the Gaia data, we analyze the formation pattern of peripherical structures of planetary systems, the elements of which are dust, asteroids, comets, and unbound...     

Binary Clusters: Theory and Observations

Astronomy Reports - The aim of this study is to search for close binary gravitationally bound pairs of open star clusters (CBOCs). We divided the observed pairs of clusters into visual binaries...     

A New-Generation Borehole Electrodynamic Seismometer for Seismological Research

This paper reports the development of a new-generation short-period borehole electrodynamic seismometer designed for research, with special emphasis on seismology and volcanology (Sobisevich et al., 2008) and for important applications (Bashilov, 2001), e.g., developing special monitoring and security systems, as well as the search for and monitoring of hydrocarbon exploration.     

Formation of Stellar Streams Due to the Decay of Star Clusters,OB Associations,and Galaxy Satellites

Astronomy Reports - This paper presents a scenario of the evolution of OB associations and star clusters from formation to decay, in the process of which they turn into stellar streams moving in...     

Proper motions of stars in the region of the Great Nebula in Orion

Six Tautenburg astrograph plates have been used to derive proper motions for 12 740 stars in the region of the Great Nebula in Orion. The Oricat catalog of proper motions and B and R photometry has been compiled, incorporating as well data from other published catalogs. The proper motions presented in different catalogs are compared. The Oricat catalog is useful for studies of features of the structure and kinematics of star clusters and groups.     

Numerical Scheme for Treatment of Uehling–Uhlenbeck Equation for Binary and Triple Interactions in Relativistic Plasma

We present a new efficient method to compute Uehling–Uhlenbeck collision integral for any two-particle and three-particle interactions in relativistic plasma with drastic improvement in computation time with respect to existingmethods. Reaction rates are compared, where possible, with the corresponding analytical expressions and another numerical results.     

The structure of the <Emphasis Type="Italic">AD</Emphasis> diagram for the Ursa Major flow

We consider kinematic inhomogeneities (stellar groups) in the corona of the Ursa Major flow. We show that the orientation of the major axis of the error ellipse for each star is defined by its position relative to its own apex. We apply the AD-diagram method suggested by us earlier; a statistical analysis confirms the existence of stellar groups in the corona of the Ursa Major flow.     

Cosmic horizon for GeV sources and photon-photon scattering

Photon-photon scattering of gamma-rays on the cosmic microwave background has been studied using the low energy approximation of the total cross section by Zdziarski and Svensson (Astrophys. J. 344:551, 1989), Svensson and Zdziarski (Astrophys. J. 349:415, 1990). Here, the cosmic horizon due to photon-photon scattering is accurately determined using the exact cross section and we find that photon-photon scattering dominates over the pair production at energies smaller than 1.68 GeV and at redshifts larger than 180.