A recoiling supermassive black hole in a powerful quasar
Abstract
Supermassive black holes (SMBH) are thought to grow through accretion of matter and mergers. Models of SMBH mergers have long suffered the final parsec problem, where SMBH binaries may stall before energy loss from gravitational waves (GW) becomes significant, leaving the pair unmerged. Direct evidence of coalesced SMBH remains elusive. Theory predicts that GW recoiling black holes can occur following a black hole merger. Here we present new and conclusive spectroscopic evidence that both the accretion disk and the broad line region in the spatially offset quasar 3C 186 are blue-shifted by the same velocity relative to the host galaxy, with a line of sight velocity of (-1310 +- 21) km/s. This is best explained by the GW recoil super-kick scenario. This confirmation of the ejection process implies that the final parsec problem is resolved in nature, providing evidence that even the most massive black holes can merge.
Cite
@article{arxiv.2501.18730,
title = {A recoiling supermassive black hole in a powerful quasar},
author = {Marco Chiaberge and Takahiro Morishita and Matteo Boschini and Stefano Bianchi and Alessandro Capetti and Gianluca Castignani and Davide Gerosa and Masahiro Konishi and Shuhei Koyama and Kosuke Kushibiki and Erini Lambrides and Eileen T. Meyer and Kentaro Motohara and Massimo Stiavelli and Hidenori Takahashi and Grant R. Tremblay and Colin Norman},
journal= {arXiv preprint arXiv:2501.18730},
year = {2025}
}
Comments
32 pages, 10 figures, submitted