Evolution of an accretion disc in binary black hole systems

Shigeo S. Kimura, Sanemichi Z. Takahashi, Kenji Toma

Research output: Contribution to journalArticlepeer-review

20 Citations (Scopus)

Abstract

We investigate evolution of an accretion disc in binary black hole (BBH) systems and possible electromagnetic counterparts of the gravitational waves from mergers of BBHs. Perna et al. proposed a novel evolutionary scenario of an accretion disc in BBHs in which a disc eventually becomes 'dead', i.e. the magnetorotational instability (MRI) becomes inactive. In their scenario, the dead disc survives until a few seconds before the merger event. We improve the dead disc model and propose another scenario, taking account of effects of the tidal torque from the companion and the critical ionization degree for MRI activation more carefully. We find that the mass of the dead disc is much lower than that in the Perna's scenario. When the binary separation sufficiently becomes small, the mass inflow induced by the tidal torque reactivates MRI, restarting mass accretion on to the black hole. We also find that this disc 'revival' happens more than thousands of years before the merger. The mass accretion induced by the tidal torque increases as the separation decreases, and a relativistic jet could be launched before the merger. The emissions from these jets are too faint compared to gamma-ray bursts, but detectable if the merger events happen within ≲10 Mpc or if the masses of the black holes are as massive as ~105M.

Original languageEnglish
Pages (from-to)4406-4413
Number of pages8
JournalMonthly Notices of the Royal Astronomical Society
Volume465
Issue number4
DOIs
Publication statusPublished - 2017 Mar 11

Keywords

  • Accretion, accretion discs
  • Black hole physics
  • Gamma-ray burst: general
  • Gravitationalwaves
  • X-rays: binaries

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

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