Quasar ON471: WSRT and VLBI Observation, Radio Spectrum

1Volvach, AE, 1Nesterov, NS
1Laboratory of Radio Astronomy, SRI Crimean Astrophysical Observatory, Katsiveli, AR Crimea, Ukraine
Kosm. nauka tehnol. 2002, 8 ;(Supplement2):279-283
Publication Language: Russian
Abstract: 
According to the observations of the quasar OH471 (z=3.4) at a frequency of 325 MHz in 1985–1996. detected variability of its radio emission. During this period, the flux density of radio emission increased 1.6 times. At a distance of 2.5 ′ to the north of the quasar, a radio source with a steep spectrum was selected. The flux density of its radio emission at a frequency of 5 GHz is 1.46 mJy, and at a frequency of 350 MHz – 14.5 mJy. According to the observations of 1964-1996. In the frequency range 0.325–90 GHz, the peculiarities of the variability of the OH 471 quasar were investigated. The spectrum had peaks at frequencies around 1 and 20 GHz. The flux density of the low-frequency component first decreased and then began to increase. The high-frequency component increased to 2.5 Jan in the late 1970s. The frequencies of the highs remained virtually unchanged. According to the results of VLBI observations at a frequency of 1.6 GHz, a structure of the type is obtained: the core is a jet 0.005 ″, oriented eastward. The object is one of the powerful quasars.
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