Spectral variability of quasars from multi-epoch photometric data in the Sloan Digital Sky Survey Stripe 82

Abstract

Aims. The study of the ensemble properties of the UV/optical broadband variability of quasars is hampered by the combined effects of the dependence of variability on timescale, rest-frame wavelength, and luminosity. Here, we present a new approach to analysing the dependence of quasar variability on rest-frame wavelengths.