Project MOMO: Multiwavelength Observations and Modelling of OJ 287
  Our project MOMO (Multiwavelength observations and modelling of OJ 287)
consists of dedicated, dense, long-term flux and spectroscopic monitoring and
deep follow-up observations of the blazar OJ 287 at >13 frequencies from the
radio to the X-ray band since late 2015. In particular, we are using Swift to
obtain optical-UV-X-ray spectral energy distributions (SEDs) and the Effelsberg
telescope to obtain radio measurements between 2 and 40 GHz. MOMO is the
densest long-term monitoring of OJ 287 involving X-rays and broad-band SEDs.
The theoretical part of the project aims at understanding jet and accretion
physics of the blazar central engine in general and the supermassive binary
black hole scenario in particular. Results are presented in a sequence of
publications and so far included: detection and detailed analysis of the bright
2016/17 and 2020 outbursts and the long-term light curve; Swift, XMM and NuSTAR
spectroscopy of the 2020 outburst around maximum; and interpretation of
selected events in the context of the binary black hole scenario of OJ 287
(papers I-IV). Here, we provide a description of the project MOMO, a summary of
previous results, the latest results, and we discuss future prospects.
