The October 2022 flare in OJ 287 and the mass of its primary black hole

@misc{valtonen2026october,
  title = {{The October 2022 flare in OJ 287 and the mass of its primary black hole}},
  author = {Mauri J. Valtonen and Staszek Zola and Manpreet Singh and Andrei V. Berdyugin and Kari Nilsson and A. Gopakumar and Alok C. Gupta and Tapio Pursimo and Alexandr E. Volvach and Marek Drozdz and Waldemar Ogloza and Rene Hudec and Martin Jel\'ınek and Jan Štrobl and Michal Zejmo and Stefano Ciprini and Daniel E. Reichart and Vladimir V. Kouprianov and Alberto Sadun and Markus Mugrauer and Katsura Matsumoto and Ryo Imazawa and Makoto Uemura and Lankeswar Dey},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2609.04998},
  eprint = {2609.04998},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2609.04998},
  note = {CC BY-NC-SA 4.0},
}

TY  - UNPB
TI  - The October 2022 flare in OJ 287 and the mass of its primary black hole
AU  - Mauri J. Valtonen
AU  - Staszek Zola
AU  - Manpreet Singh
AU  - Andrei V. Berdyugin
AU  - Kari Nilsson
AU  - A. Gopakumar
AU  - Alok C. Gupta
AU  - Tapio Pursimo
AU  - Alexandr E. Volvach
AU  - Marek Drozdz
AU  - Waldemar Ogloza
AU  - Rene Hudec
AU  - Martin Jel\'ınek
AU  - Jan Štrobl
AU  - Michal Zejmo
AU  - Stefano Ciprini
AU  - Daniel E. Reichart
AU  - Vladimir V. Kouprianov
AU  - Alberto Sadun
AU  - Markus Mugrauer
AU  - Katsura Matsumoto
AU  - Ryo Imazawa
AU  - Makoto Uemura
AU  - Lankeswar Dey
PY  - 2026
DA  - 2026/09/04
PB  - arXiv
DO  - 10.48550/arxiv.2609.04998
UR  - https://arxiv.org/abs/2609.04998
AB  - The bright blazar OJ~287 has demonstrated a sequence of flares, which are well explained by a quasi-Keplerian orbit model. The flares are associated with the impact of the secondary on the accretion disk of the primary. The orbit must precess in order to produce the correct sequence of flares, and from the precession rate we calculate the mass of the primary. This precession rate gives the mass of the primary M_BH = (18.35±0.05) × 10^9 M_⊙. Two kinds of flares have been identified: direct flares from the impacts, and tidal flares arising from an increased accretion flow into the jet. The precession rate and the primary black hole mass may be independently determined from both sets of flares; the tidal flare of October 2022 was recommended for an intense campaign for this reason. This paper describes these observations over a wide spectral range. We show that the October 2022 flare fits the expectations for a tidal flare and thus supports the earlier determination of the mass of the binary black hole system in OJ 287. The mass of the primary may also be deduced from secondary indicators such as the correlation with the hydrogen line strength and the black hole mass. These studies require that the mass is above M_BH ∼ 10^10 M_⊙, but do not specify the value more exactly.
ER  -