Volvach O. Transient radiation of extragalactic sources from the observations in the microwave range

The thesis is devoted to establishing the nature of the physical processes that occur in the nuclear area of active galaxies and lead to enormous energy, determination of physical characteristics and parameters of the medium in the central regions of AGN, the study of the microstructure and its relationship with variations of integral fluxes of compact extragalactic radio sources. The basis of research is new observations of these objects, obtained using the radio telescope RT-22 SRI "Crimean Astrophysical Observatory". Variations in the radio flux of 0716+714, 3C454.3, 3C120, OJ287, 1308+326, and BL Lac on various time scales from decades to a year are analyzed using long-term monitoring data at five frequencies from 4.8 to 36.8 GHz. A spectral analysis of the light curves reveals the presence of periodic components. These data are used to construct kinematic models for AGN using values for the orbital and processional periods of binary systems consisting of super massive black holes. Radio and optical data are used to analyze the development of the flare in the blazar 3С 454.3 observed in 2004-2007. A detailed correspondence between the optical and radio flares is established, with a time delay that depends on the observing frequency. The coordinated synchronous observations of AGN 0133+476, 1633+382, 2134+004, 2145+067 і 2251+158 in the radio and optical, aimed at searching for fast (intraday) flux variations and possible correlations in the flux variations in different wavebands were presented. The combined analysis of integral flux density variations and milliarcsecond scale structures was performed for 32 sources. It is found that for a number of sources the flux density bursts at high frequencies are not accompanied by emerging new VLBI jet component, while for some objects the flux density changes occur quasi-simultaneously at different frequencies and the bursts are accompanied by ejecting new VLBI component. Observations of a sample of sources from the preliminary "Radioastron" catalog were obtained at 22.2 and 36.8 GHz on the RT-22. We have plotted the logN-logS dependence down to the flux levels of about 0.1 Jy using the survey data of near 22 GHz, where there is reduction in the density of cosmological sources in relation to not evolving Euclidean universe.