The Optical Variability of the BL Lac AO 0235+164

Abstract

Abstract:In this work, we present optical R band observations of AO 0235+164 carried out during the period of November 2006 to December 2012 using the Ap6E CCD camera attached to the primary focus of the 70 cm meniscus telescope at Abastumani Observatory, Georgia. It shows a large variation of ∆R = 4.88 mag (14.19-19.07 mag) and a short time scale of ∆T v = 73.5 min during our monitoring period. When periodicity analysis methods are applied to the R-band data from both historic and our observations, periods P 1 = 8.26 yr and P 2 = 0.54 yr are found.

A γ-ray Quasi-periodic Modulation in the Blazar PKS 0301–243?

“…The periodic variabilities of blazars have been investigated extensively in the optical band (e.g., Bai et al 1998Bai et al , 1999Fan & Lin 2000;Xie et al 2008;Li et al 2009;Urry 2011;King et al 2013;Zhang et al 2014;Bhatta et al 2016;Fan et al 2016). An interesting case is that of OJ 287, which has a ∼12 yr period cycle (Kidger et al 1992;Valtonen et al 2006).…”