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Spectral Variability of Quasars in the Optical Band

Published online by Cambridge University Press:  12 April 2016

Dario Trèvese  and
Fausto Vagnetti
Dario Trèvese
Affiliation:
Dipartimento di Fisica, Università di Roma“La Sapienza”, Piazzale A.Moro 2, 2-00185 Roma, Italy
Fausto Vagnetti
Affiliation:
Dipartimento di Fisica, Università di Roma“Tor Vergata”, Via della Ricerca Scientifica 1, I-00133 Roma, Italy

Abstract

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We performed a new analysis of the В and R light curves of a sample of PG QSOs. We confirm a variability-redshift correlation and its interpretation in terms of spectral variability. We find an intra-QSO and an inter-QSO α;-L correlation. The former can be explained neither by presence of the host galaxy nor by changes of the accretion rate. Hot spots due to accretion disk instabilities could explain the observations.

Type
Part 1. Optical Surveys for AGN
Information
International Astronomical Union Colloquium , Volume 184: AGN Surveys , 2002 , pp. 81 - 86
Copyright
Copyright © Astronomical Society of the Pacific 2002

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