# The Host Galaxy of OJ 287 Revealed by Optical and Near-infrared Imaging

DOI:
10.3847/1538-4357/abbda1
Publication date:
01/12/2020
Main author:
Nilsson, K.
IAA authors:
Authors:
Nilsson, K.;Kotilainen, J.;Valtonen, M.;Gomez, J. L.;Castro-Tirado, A. J.;Drozdz, M.;Gopakumar, A.;Jeong, S.;Kidger, M.;Komossa, S.;Mathur, S.;Park, I. H.;Reichart, D. E.;Zola, S.
Journal:
The Astrophysical Journal
Refereed:
Yes
Publication type:
Article
Volume:
904
Pages:
102
Abstract:
The BL Lacertae object OJ 287 (z = 0.306) has unique double-peaked optical outbursts every ∼12 yr, and it presents one of the best cases for a small-separation binary supermassive black hole (SMBH) system, with an extremely massive primary $\mathrm{log}({M}_{\mathrm{BH}}/{M}_{\odot })\sim 10.3$ . However, the host galaxy is unresolved or only marginally detected in all optical studies so far, indicating a large deviation from the bulge mass—SMBH mass relation. We have obtained deep, high spatial resolution i-band and K-band images of OJ 287 when the target was in a low state, which enable us to detect the host galaxy. We find the broadband photometry of the host to be consistent with an early-type galaxy with M<SUB>R</SUB> = -22.5 and M<SUB>K</SUB> = -25.2, placing it in the middle of the host galaxy luminosity distribution of BL Lacertae objects. The central supermassive black hole is clearly overmassive for a host galaxy of that luminosity, but not unprecedented, given some recent findings of other 'overmassive' black holes in nearby galaxies.
Database: