Evolution of flux density and parsec-scale structure of compact extragalactic radio sources from monitoring results at 4.8–36.8 GHz and imaging on the basis of geodetic VLBI observations

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Astronomy and Astrophysics
1Volvach, AE, 2Pushkarev, AB, 1Volvach, LN, 3Aller, HD, 3Aller, MF
1Laboratory of Radio Astronomy, SRI Crimean Astrophysical Observatory, Katsiveli, AR Crimea, Ukraine
2Astro Space Center of P.N. Lebedev Physics Institute, Moscow, Russia
3Radio Observatory of the Michigan University, AnnArbor, USA
Kosm. nauka tehnol. 2009, 15 ;(4):33-57
https://doi.org/10.15407/knit2009.04.033
Publication Language: Russian
Abstract: 
We present some results on the variability of radio sources which from continuous monitoring observations made at 4.8–36.8 GHz at the Crimean Astrophysical Observatory (Ukraine) and Michigan Radio Astronomy Observatory (USA), and from international geodetic VLBI observations carried out at 2 and 8 GHz. 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-simul-taneously at different frequencies and the bursts are accompanied by ejecting new VLBI component.
Keywords: extragalactic radio sources, flux density, monitoring
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