... astro-ph/0003002 We cross-identified the ROSAT Bright Source Catalog (RBSC) and the NRAO VLA Sky Survey (NVSS) to construct the RBSC-NVSS sample of the brightest X-ray sources (~0.1 counts s^{-1} ~= 10^{-12} ergs cm^-2s^-1 in the 0.1--2.4 keV band) that are also radio sources (S ~= 2.5 mJy at 1.4 GHz) in the 7.8 sr of extragalactic sky with |b| > 15deg and DEC > -40deg. ... We used the more accurate radio positions to make reliable X-ray/radio/optical identifications down to the POSS plate limits. ...

... LABORATORY OF RADIO ASTRONOMICAL OBSERVATIONS . Radio sources identification is one of the most important tasks of the current radio astrophysics. ... Optical idetification. ... Optical identifications of subsample of steep spectra radio sources from RC catalog using 6m SAO telescope of SAO RAS: optical observations. ... Astronomy Reports. ... Identification of radio sources with data of various radio catalogs allows one to construct continual spectrum of the object and its radio structure. ...

... Ultraluminous X-ray sources (ULXs) are located in external galaxies, their X-ray luminosities (10 39 - 10 41 erg/s) are thousand times greater than those of brightest black holes in the Galaxy. ULXs may be supercritical accretion disks around black holes of stellar masses (~10 Solar masses) like that in SS433, or they may be a hypothetical intermediate-mass black holes (hundreds - thousands Solar masses) with standard accretion disks. ... 2) The ULX progenitors were ejected from the star clusters. ...

... In LABORATORY OF RADIO ASTROPHYSICS OF SPECIAL ASTROPHYSICAL OBSERVATORY OF RAS . ... History . ... Current problems of the group research interests: . study for cosmic microwave background, . study of radio galaxies (identification, evolution, statistical investigation of population), . investigation of the RATAN-600 antenna, . observations in the survey mode with RATAN-600 and their analysis, . creation of the software for data analysis. vo @ sao.ru ( Oleg Verkhodanov ) ...