Understanding extreme quasar optical variability with CRTS: I. Major AGN flares

Understand

There is a large degree of variety in the optical variability of quasars and it is unclear whether this is all attributable to a single (set of) physical mechanism(s).

• We present the results of a systematic search for major flares in AGN in the Catalina Real-time Transient Survey as part of a broader study into extreme quasar variability.
• Such flares are defined in a quantitative manner as being atop of the normal, stochastic variability of quasars.
• We have identified 51 events from over 900,000 known quasars and high probability quasar candidates, typically lasting 900 days and with a median peak amplitude of $\Delta m = 1.25$ mag.