Перегляд за Автор "Donskykh, A."

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  • Ескіз
    Документ
    ANALYSIS OF THE VARIABILITY AND THE SPECTRUM OF PERIODS OF EXTRAGALACTIC SOURCE OJ 287 IN THE RADIO WAVES
    (Astroprint, 2013) Donskykh, A.; Ryabov, Myhaylo I.; Sukharev, A. L.; Aller, M. F.; Рябов, Михайло Іванович
    We analyzed long-term monitoring of data flux of extragalactic source OJ 287 obtained at frequencies of 14.5 GHz (1974-2011), 8 GHz (1971-2011), 4.8GHz and (1979-2010), on the RT-26, University of Michigan, USA. Variability of the flux of the radio source was investigated by applying wavelet analysis. There were identified long-period (in the range of 3.6 to 13.6 years) and short (in the range from 1.2 to 1.8 years) components at all studied frequencies and it was determined the time of their existence. The "spectra periods" for each year of observation were built to assess the contribution of individual periods in the formation of the most powerful phase of activity of the radio source. The dynamics of the manifestations of active periods at different frequencies was observed. The obtained data was compared with the results of MOJAVE VLBI monitoring for the period of 1995-2012 years at a frequency of 15.4 GHz. It allowed to investigate the structure of emissions during periods of manifestation activity maxima.
  • Ескіз
    Документ
    VARIABILITY OF THE EXTRAGALACTIC RADIO SOURCES 3С120, СТА102, DA55 AND OJ287 ON CENTIMETER WAVES AND ITS CONNECTIONS WITH THE DATA OF VLBI OBSERVATIONS
    (Astroprint, 2012) Ryabov, Myhaylo I.; Donskykh, A.; Sukharev, A. L.; Aller, M. F.; Рябов, Михайло Іванович
    ABSTRACT. By data of the long-term monitoring (30-40 years) fluxes of extragalactic radio sources 3C120, CTA102, DA55 and OJ287 received on the RT-26, University of Michigan present results of data processing with use the wavelet analysis. Received analysis of trend and short-time components of the flux density changes in the studied frequencies 14.5, 8 and 4.8 GHz. For each time components on all frequencies found values of main periods and time of their existence, integrated power spectra for the phases activity for radio sources was built. From the results of VLBI observations in sources with long jets (3C120 and CTA102) detected quasi-periodic structures brighter components. Their appearance is linked to the dynamics of the interaction of shock waves in the jet emission from the cores. Quasi-periodic structures in the jet can be formed as a result of a return standing wave.