Stellar hardening of massive black hole binaries: the impact of the host rotation

Abstract

Massive black hole binaries (MBHBs) with masses of ~ 10^4 to ~ 10^10 of solar masses are one of the main targets for currently operating and forthcoming space-borne gravitational wave observatories. In this paper, we explore the effect of the stellar host rotation on the bound binary hardening efficiency, driven by three-body stellar interactions. As seen in previous studies, we find that the centre of mass (CoM) of a prograde MBHB embedded in a rotating environment starts moving on a nearly circular orbit about the centre of the system shortly after the MBHB binding. In our runs, the oscillation radius is approximately 0.25 ( approximately 0.1) times the binary influence radius for equal mass MBHBs (MBHBs with mass ratio 1:4). Conversely, retrograde binaries remain anchored about the centre of the host. The binary shrinking rate is twice as fast when the binary CoM exhibits a net orbital motion, owing to a more efficient loss cone repopulation even in our spherical stellar systems. We develop a model that captures the CoM oscillations of prograde binaries; we argue that the CoM angular momentum gain per time unit scales with the internal binary angular momentum, so that most of the displacement is induced by stellar interactions occurring around the time of MBHB binding, while the subsequent angular momentum enhancement gets eventually quashed by the effect of dynamical friction. The effect of the background rotation on the MBHB evolution may be relevant for LISA sources, that are expected to form in significantly rotating stellar systems.

arXiv comment10 pages, 9 figures, 2 tables. Accepted for publication on MNRAS

References in corpus (45)

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies
• The many lives of active galactic nuclei: cooling flows, black holes and the luminosities and colours of galaxies
• A Cosmological Framework for the Co-Evolution of Quasars, Supermassive Black Holes, and Elliptical Galaxies: I. Galaxy Mergers & Quasar Activity
• A Unified Model for the Evolution of Galaxies and Quasars
• The Assembly and Merging History of Supermassive Black Holes in Hierarchical Models of Galaxy Formation
• The NANOGrav 12.5-year Data Set: Search For An Isotropic Stochastic Gravitational-Wave Background
• Formation of Galactic Nuclei
• The stochastic gravitational-wave background from massive black hole binary systems: implications for observations with Pulsar Timing Arrays
• The dynamical evolution of massive black hole binaries - I. Hardening in a fixed stellar background
• Science with the space-based interferometer eLISA. I: Supermassive black hole binaries
• High-precision timing of 42 millisecond pulsars with the European Pulsar Timing Array
• Long Term Evolution of Massive Black Hole Binaries
• The International Pulsar Timing Array: Second data release
• Efficient Merger of Binary Supermassive Black Holes in Non-Axisymmetric Galaxies
• Massive Black Hole Binary Evolution
• Efficient Merger of Binary Supermassive Black Holes in Merging Galaxies
• Chaotic Loss Cones, Black Hole Fueling and the M-Sigma Relation
• Interaction of massive black hole binaries with their stellar environment: I. Ejection of hypervelocity stars
• Fast coalescence of massive black hole binaries from mergers of galactic nuclei: implications for low-frequency gravitational-wave astrophysics
• Supermassive Black Hole Binary Evolution in Axisymmetric Galaxies: the final parsec problem is not a problem
• The final-parsec problem in the collisionless limit
• eLISA eccentricity measurements as tracers of binary black hole formation
• Massive black hole binaries: dynamical evolution and observational signatures
• LISA double black holes: Dynamics in gaseous nuclear discs
• 6th and 8th Order Hermite Integrator for N-body Simulations
• Interaction of massive black hole binaries with their stellar environment: II. Loss-cone depletion and binary orbital decay
• Collisionless loss-cone refilling: there is no final parsec problem
• Interaction of massive black hole binaries with their stellar environment: III. Scattering of bound stars
• Brownian Motion of a Massive Binary
• Galaxy Rotation and Rapid Supermassive Black Hole Binary Coalescence
• Massive black hole binary eccentricity in rotating stellar systems
• A fully parallel, high precision, N-body code running on hybrid computing platforms
• The loss cone problem in axisymmetric nuclei
• Effects of Wandering on the Coalescence of Black Hole Binaries in Galactic Centers
• Brownian motion of massive black hole binaries and the final parsec problem
• Galaxy Rotation and Supermassive Black Hole Binary Evolution
• The Link Between Ejected Stars, Hardening and Eccentricity Growth of Super Massive Black Holes in Galactic Nuclei
• The influence of Massive Black Hole Binaries on the Morphology of Merger Remnants
• Inward Bound: The incredible journey of massive black holes as they pair and merge; I. The effect of mass ratio in flattened rotating galactic nuclei
• Evolution Of Binary Supermassive Black Holes In Rotating Nuclei
• Massive black hole binary plane reorientation in rotating stellar systems
• Dynamical friction-driven orbital circularisation in rotating discs: a semi-analytical description
• Star cluster disruption by a massive black hole binary
• Dynamical evolution of massive perturbers in realistic multi-component galaxy models I: implementation and validation

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