Radio Physics and Radio Astronomy

INVESTIGATION OF INTRADAY VARIABILITY OF ACTIVE GALACTIC NUCLEI IN OPTICAL AND RADIO RANGES

RESUMO

Joint and synchronous radio and optical observations of active galactic nuclei aimed at detecting fast intraday flux density variabilities (IDV) and searching for their possible correlation are carried out. The radio sources 0133+476, 1633+382, 2134+004, 2145+067 and 2251+158 were observed with the CrAO RT-22 at 22.2 and 36.8 GHz and with the SAO RAS 1-m Zeiss-1000 reflector with a CCD camera in 2004-2006. The variations in the R-band are within 0.2^m at time scale 15 min in 0133+476 and 0.25^m at time scale 20 min in 2251+158. In the rest of sources no significant flux density variability was observed. In the radio band, the flux density variability of the sources 0133+476, 2134+004 is 1.5 Jy at time scale 15 min, and 3 Jy at time scale 2 h in 2145+067. The chaotic fluctuations of the flux density observed in 2251+158 are 2÷2.5 Jy at time scale 0.5 h. No correlation is observed between the variability in optical and radio wavelengths.

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