Optical Observations of Correlated Outburst Activity in BL Lacertae
ATel #9600; Thomas J. Balonek, Ryan W. Stahlin, Katie J. Chapman, Alina Sabyr, Saiyang Zhang (Colgate Univ)
on 6 Oct 2016; 06:13 UT
Credential Certification: Thomas J. Balonek (tbalonek@colgate.edu)
Subjects: Optical, AGN, Blazar, Quasar
We report an optical (R) outburst in the blazar BL Lacertae likely associated with the recently reported gamma ray flare on 2016 October 5 (Mukherjee, ATel #9599). Since early September, when BL Lac was at a local minimum (R ~ 14.1-14.2), it has increased in brightness, rising to R ~ 12.9-13.0 on 2016 October 4, 5, 6 (UT). On 2016 October 6, continuous observations over 6 hours show only minor variations (ΔR < 0.1). Several smaller flares were were superimposed on the month-long rise, the brightest peaking around September 22-23 at R ~ 13.2, followed by a fading of 0.4 magnitude in 2 days. The pre-outburst minimum corresponds to the faintest we have observed BL Lac since a local minimum of similar brightness in mid-2014; the peak is the brightest we have observed since a comparable outburst that peaked in late May 2016. All observations were obtained using the Ferson 0.4-m telescope equipped with a FLI PL1001 CCD camera at Colgate University's Foggy Bottom University in Hamilton, NY.
Student research participation at Colgate University is supported by the NASA / New York Space Grant, and Colgate University Schlichting fellowships and a Research Council grant.
Further observations are encouraged, as this source frequently exhibits multi-wavelength intra-day variability.
