2015/07/31 by Girish Kulkarni, Abraham Loeb · 1 citation
Physics and Astronomy · #Accretion (finance) #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Binary black hole #Circumbinary planet #Galaxy #Gravitational wave #Physics #Planet #Pulsar #Pulsars and Gravitational Waves Research #Redshift #Superluminal motion #Supermassive black hole #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stv2940
published as MNRAS 2016 456 3964 · Corrected LaTeX error that prevented references from showing up correctly; otherwise identical to v2
openalex publication_date 2016/01/14 · openalex created_date 2016/06/24 · arxiv created 2017/08/31 · arxiv updated 2017/09/01 · openalex updated_date 2026/08/06
We study a novel electromagnetic signature of supermassive black hole (BH) binaries whose inspiral starts being dominated by gravitational wave (GW) emission. Recent simulations suggest that the binary's member BHs can continue to accrete gas from the circumbinary accretion disc in this phase of the binary's evolution, all the way until coalescence. If one of the binary members produces a radio jet as a result of accretion, the jet precesses along a biconical surface due to the binary's orbital motion. When the binary enters the GW phase of its evolution, the opening angle widens, the jet exhibits milliarcsecond-scale wiggles, and the conical surface of jet precession is twisted due to apparent superluminal motion. The rapidly increasing orbital velocity of the binary gives the jet an appearance of a ‘chirp’. This helical chirping morphology of the jet can be used to infer the binary parameters. For binaries with mass 107–1010 M⊙ at redshifts z < 0.5, monitoring these features in current and archival data will place a lower limit on sources that could be detected by Evolved Laser Interferometer Space Antenna and Pulsar Timing Arrays. In the future, microarcsecond interferometry with the Square Kilometre Array will increase the potential usefulness of this technique.