Single and Binary Black Holes and their Influence on Nuclear Structure

Astrophysics, abstract
astro-ph/0301257

From: David Merritt <merritt@physics.rutgers.edu>

Date: Tue, 14 Jan 2003 15:38:38 GMT   (65kb)

Authors:
David Merritt (Rutgers University)

Comments: 10 pages, 4 figures, uses emulateapj.sty, onecolfloat.sty. An
abridged version of this article will appear in Carnegie Observatories
Astrophysics Series, Vol. 1: “Coevolution of Black Holes and Galaxies,”
edited by L. C. Ho (Cambridge: Cambridge Univ. Press)

Report-no: Rutgers Astrophysics Preprint Series No. 379

Massive central objects affect both the structure and evolution of galactic
nuclei. Adiabatic growth of black holes generates power-law central density
profiles with logarithmic slopes in the range from ~1.5 to ~2.5, in good
agreement with the profiles observed in the nuclei of galaxies fainter than
visual magnitude -20. However the shallow nuclear profiles of bright galaxies
require a different explanation. Binary black holes are an inevitable result of
galactic mergers, and the ejection of stars by a massive binary displaces a
mass of order the binary’s own mass, creating a core or shallow power-law cusp.
This model is at least crudely consistent with core sizes in bright galaxies.
Uncertainties remain about the effectiveness of stellar- and gas-dynamical
processes at inducing coalescence of binary black holes, and uncoalesced
binaries may be common in low-density nuclei.

References and citations for this submission:

SLAC-SPIRES HEP (refers to ,
cited by, arXiv reformatted)