Abstract:
We have analyzed the optical light curves of the blazar OJ 287 obtained with the Transiting Exoplanet Survey
Satellite over about 80 days from 2021 October 13 to December 31, with an unprecedented sampling of 2 minutes.
Although significant variability has been found during the entire period, we have detected two exceptional flares
with flux nearly doubling and then nearly tripling over 2 days in the middle of 2021 November. We went through
the light-curve analysis using the excess variance, generalized Lomb–Scargle periodogram, and continuous
autoregressive moving average methods and estimated the flux halving/doubling timescales. The most probable
shortest variability timescale was found to be 0.38 days in the rising phase of the first flare. We briefly discuss
some emission models for the variability in radio-loud active galactic nuclei that could be capable of producing
such fast flares.
