MOMO V. Effelsberg, Swift and Fermi study of the blazar and supermassive binary black hole candidate OJ 287 in a period of high activity

Abstract

We report results from our ongoing project MOMO (Multiwavelength Observations and Modelling of OJ 287). In this latest publication of a sequence, we combine our Swift UVOT--XRT and Effelsberg radio data (2.6-44 GHz) between 2019 and 2022.04 with public SMA data and gamma-ray data from the Fermi satellite. The observational epoch covers OJ 287 in a high state of activity from radio to X-rays. The epoch also covers two major events predicted by the binary supermassive black hole (SMBH) model of OJ 287. Spectral and timing analyses clearly establish: a new UV-optical minimum state in 2021 December at an epoch where the secondary SMBH is predicted to cross the disk surrounding the primary SMBH; an overall low level of gamma-ray activity in comparison to pre-2017 epochs; the presence of a remarkable, long-lasting UV--optical flare event of intermediate amplitude in 2020--2021; a high level of activity in the radio band with multiple flares; and particularly a bright, ongoing radio flare peaking in 2021 November that may be associated with a gamma-ray flare, the strongest in 6 years. Several explanations for the UV--optical minimum state are explored, including the possibility that a secondary SMBH launches a temporary jet, but the observations are best explained by variability associated with the main jet.

16 pages, 11 figures. Published in MNRAS (submitted in January, accepted in March)

References in corpus (17)

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• Explaining temporal variations in the jet position angle of the blazar OJ 287 using its binary black hole central engine model
• X-ray spectral components of the blazar and binary black hole candidate OJ 287 (2005-2020)
• Black hole science with the Laser Interferometer Space Antenna
• MOMO IV: The complete Swift X-ray and UV/optical light curve and characteristic variability of the blazar OJ 287 during the last two decades
• Spectroscopic classification, variability and SED of the Fermi-detected CSS 3C 286: the radio-loudest NLS1 galaxy?
• A comprehensive study of 2019-2020 flare of OJ 287 using AstroSat, Swift, and NuSTAR

Cited by in corpus (7)

• Absence of the predicted 2022 October outburst of OJ 287 and implications for binary SMBH scenarios
• MOMO VI: Multifrequency radio variability of the blazar OJ 287 from 2015-2022, absence of predicted 2021 precursor-flare activity, and a new binary interpretation of the 2016/2017 outburst
• Refining the 2022 OJ 287 impact flare arrival epoch
• Observational Implications of OJ 287's Predicted 2022 Disk Impact in the Black Hole Binary Model
• Clues on the nature of the quasi-periodic optical outbursts of the blazar OJ 287
• Multiwavelength astrophysics of the blazar OJ 287 and the project MOMO
• Simultaneous Optical to X-ray Spectra of OJ 287: Insights into X-ray spectral changes and particle spectra