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arXiv · 1304.2835

The spectral variability in radio-loud quasars

Minfeng Gu
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Abstract

The spectral variability of a sample of 44 flat-spectrum radio quasars (FSRQs) and 18 steep-spectrum radio quasars (SSRQs) in the SDSS stripe 82 region is investigated. Twenty-five of 44 FSRQs show a bluer-when-brighter trend (BWB), while only one FSRQ shows a redder-when-brighter trend, which is in contrast to our previous results. Eight of 18 SSRQs display a BWB. We found an anti-correlation between the Eddington ratio and the variability amplitude in r band for SSRQs, which is similar to that in radio-quiet AGNs. This implies that the thermal emission from the accretion disk may be responsible for the variability in SSRQs. The spectral variability from the SDSS multi-epoch spectroscopy also shows BWB for several SSRQs, consistent with that from photometry.

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Minfeng Gu. 2013-04-10. The spectral variability in radio-loud quasars. https://doi.org/10.1007/s12036-014-9232-x

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