A Search for QPOs in the Blazar OJ287: Preliminary Results from the 2015/2016 Observing Campaign


Zola S., Valtonen M., Bhatta G., Goyal A., Debski B., Baran A., ...More

GALAXIES, vol.4, no.4, 2016 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 4 Issue: 4
  • Publication Date: 2016
  • Doi Number: 10.3390/galaxies4040041
  • Journal Name: GALAXIES
  • Journal Indexes: Emerging Sources Citation Index, Scopus
  • Keywords: galaxies: active, BL Lacertae objects: individual (OJ287), supermassive black holes, GENERAL-RELATIVITY, TIME-SERIES, SPACED DATA, OJ 287

Abstract

We analyse the light curve in the R band of the blazar OJ287, gathered during the 2015/2016 observing season. We did a search for quasi-periodic oscillations (QPOs) using several methods over a wide range of timescales. No statistically significant periods were found in the high-frequency domain both in the ground-based data and in Kepler observations. In the longer-period domain, the Lomb-Scargle periodogram revealed several peaks above the 99% significance level. The longest one-about 95 days-corresponds to the innermost stable circular orbit (ISCO) period of the more massive black hole. The 43-day period could be an alias, or it can be attributed to accretion in the form of a two-armed spiral wave.