Orbital orientation evolution of massive binary black holes at the centres of non-spherical galaxies

Abstract

At the centre of a spherical and kinematically isotropic galaxy, the orientation of a massive binary black hole (BBH) orbit (i.e., the direction of the BBH orbital angular momentum) undergoes a random walk. If the stars in a spherical system have a non-zero total angular momentum, the BBH orbital orientation evolves towards aligning with the total stellar angular momentum direction. In this paper, we show that a triaxial galaxy has an alignment-erasing effect, that is, the alignment of the BBH orientations towards the galaxy rotation axis can be decreased significantly or erased. We also show that in a non-rotating axisymmetric galaxy, the BBH orbital orientation evolves towards the axisymmetric axis and precesses about it in a retrograde direction. Our results provide a step towards understanding the spin orientations of the final merged BH (and hence probable orientation of any jet produced) within its host galaxy, and may help to constrain the recoiling velocity of the merged BH arose from gravitational wave radiation as well.

16 pages, 9 figures, MNRAS accepted

References in corpus (9)

• Alignment of the spins of supermassive black holes prior to coalescence
• Supermassive black hole binaries in gaseous and stellar circumnuclear discs: orbital dynamics and gas accretion
• The Redshift Evolution of Wet, Dry, and Mixed Galaxy Mergers from Close Galaxy Pairs in the DEEP2 Galaxy Redshift Survey
• Interaction of massive black hole binaries with their stellar environment: I. Ejection of hypervelocity stars
• Self consistent model for the evolution of eccentric massive black hole binaries in stellar environments: implications for gravitational wave observations
• A supermassive binary black hole with triple disks
• Supermassive Black Hole Growth and Merger Rates from Cosmological N-body Simulations
• Intrinsic Axis Ratio Distribution of Early-type Galaxies From Sloan Digital Sky Survey
• Merging of a massive black hole binary II

Cited by in corpus (9)

• The final-parsec problem in the collisionless limit
• Dynamical evolution of cosmic supermassive binary black holes and their gravitational wave radiation
• The Link Between Ejected Stars, Hardening and Eccentricity Growth of Super Massive Black Holes in Galactic Nuclei
• Evolution Of Binary Supermassive Black Holes In Rotating Nuclei
• Constraints on the Galactic Centre environment from \textit{Gaia} hypervelocity stars III: Insights on a possible companion to Sgr A*
• Evolution of supermassive black hole binaries and tidal disruption rates in nonspherical galactic nuclei
• Effect of accreting tidally disrupted stars on the spin evolution of $\sim 10^6{M}_{\odot }$ black holes
• Properties of loss cone stars in a cosmological galaxy merger remnant
• Cosmic distributions of stellar tidal disruptions by massive black holes at galactic centers