Fossil Gas and the Electromagnetic Precursor of Supermassive Binary Black Hole Mergers

Abstract

Using a one-dimensional height integrated model, we calculate the evolution of an unequal mass binary black hole with a coplanar gas disk that contains a gap due to the presence of the secondary black hole. Viscous evolution of the outer circumbinary disk initially hardens the binary, while the inner disk drains onto the primary (central) black hole. As long as the inner disk remains cool and thin at low ${\dot{M}}_{\mathrm{ext}}$ (rather than becoming hot and geometrically thick), the mass of the inner disk reaches an asymptotic mass typically $\sim 10^{-3}-10^{-4}\Msun$. Once the semimajor axis shrinks below a critical value, angular momentum losses from gravitational waves dominate over viscous transport in hardening the binary. The inner disk then no longer responds viscously to the inspiraling black holes. Instead, tidal interactions with the secondary rapidly drive the inner disk into the primary. Tidal and viscous dissipation in the inner disk lead to a late time brightening in luminosity $L\propto t_{\mathrm{minus}}^{5/4}$, where $t_{\mathrm{minus}}$ is the time prior to the final merger. This late time brightening peaks $\sim 1$ day prior to the final merger at $\sim 0.1L_{\mathrm{Edd}}$. This behavior is relatively robust because of self regulation in the coupled viscous-gravitational evolution of such binary systems. It constitutes a unique electromagnetic signature of a binary supermassive black hole merger and may allow the host galaxy to be identified if used in conjunction with the Laser Interferometric Space Antenna (LISA) localization.

11 pages, 6 figures, submitted to MNRAS

References in corpus (16)

• Massive black hole binary mergers within sub-pc scale gas discs
• Supermassive recoil velocities for binary black-hole mergers with antialigned spins
• The Population of Viscosity- and Gravitational Wave-Driven Supermassive Black Hole Binaries Among Luminous AGN
• Supermassive black hole binaries in gaseous and stellar circumnuclear discs: orbital dynamics and gas accretion
• Getting a kick out of numerical relativity
• Observable Signatures of a Black Hole Ejected by Gravitational Radiation Recoil in a Galaxy Merger
• Prompt Shocks in the Gas Disk Around a Recoiling Supermassive Black Hole Binary
• Pre-Merger Localization of Gravitational-Wave Standard Sirens With LISA: Triggered Search for an Electromagnetic Counterpart
• Dual black holes in merger remnants. I: linking accretion to dynamics
• Binary Black Hole Merger in Galactic Nuclei: Post-Newtonian Simulations
• Binary black hole merger: symmetry and the spin expansion
• Localizing coalescing massive black hole binaries with gravitational waves
• Reaction of Accretion Disks to Abrupt Mass Loss During Binary Black Hole Merger
• Pre-Merger Localization of Gravitational-Wave Standard Sirens With LISA I: Harmonic Mode Decomposition
• The Origin of the Young Stars in the Nucleus of M31
• Gas Shepherding by an Infalling Satellite

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