Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2010-09-24
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
30 pages, 18 figures. Accepted for publication in MNRAS
Scientific paper
Gravitational-wave (GW) recoil of merging supermassive black holes (SMBHs) may influence the co-evolution of SMBHs and their host galaxies. We examine this possibility using SPH/N-body simulations of gaseous galaxy mergers in which the merged BH receives a recoil kick. This enables us to follow recoiling BHs in self-consistent, evolving merger remnants. In contrast to recent studies on similar topics, we conduct a large parameter study, generating a suite of over 200 simulations with more than 60 merger models and a range of recoil velocities (vk). Our main results are as follows. (1) BHs kicked at nearly the central escape speed (vesc) may oscillate on large orbits for up to a Hubble time, but in gas-rich mergers, BHs kicked with up to ~ 0.7 vesc may be confined to the central few kpc of the galaxy, owing to gas drag and steep central potentials. (2) vesc in gas-rich mergers may increase rapidly during final coalescence, in which case trajectories may depend on the timing of the BH merger relative to the formation of the potential well. (3) Recoil events generally reduce the lifetimes of bright active galactic nuclei (AGN), but may actually extend AGN lifetimes at lower luminosities. (4) Kinematically-offset AGN (v > 800 km s^-1) may be observable for up to ~ 10 Myr either immediately after the recoil or during pericentric passages through a gas-rich remnant. (5) Spatially-offset AGN (R > 1 kpc) generally have low luminosities and lifetimes of ~ 1 - 100 Myr. (6) Rapidly-recoiling BHs may be up to ~ 5 times less massive than their stationary counterparts. This lowers the normalization of the M-sigma relation and contributes to both intrinsic and overall scatter. (7) Finally, the displacement of AGN feedback after a recoil event enhances central star formation rates, thereby extending the starburst phase of the merger and creating a denser stellar cusp. [Abridged.]
Blecha Laura
Cox Thomas J.
Hernquist Lars
Loeb Abraham
No associations
LandOfFree
Recoiling Black Holes in Merging Galaxies: Relationship to AGN Lifetimes, Starbursts, and the M-sigma Relation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Recoiling Black Holes in Merging Galaxies: Relationship to AGN Lifetimes, Starbursts, and the M-sigma Relation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Recoiling Black Holes in Merging Galaxies: Relationship to AGN Lifetimes, Starbursts, and the M-sigma Relation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-695418