Rapid Merger of Binary Primordial Black Holes: an Implication for GW150914
Abstract
We propose a new scenario for the evolution of a binary of primordial black holes (PBHs). We consider a dynamical friction by ambient dark matter, scattering of dark matter particles with a highly eccentric orbit besides the standard two-body relaxation process to refill the loss cone, and interaction between the binary and a circumbinary disk, assuming that PBHs do not constitute the bulk of dark matter. Binary PBHs lose the energy and angular momentum by these processes, which could be sufficiently efficient for a typical configuration. Such a binary coalesces due to the gravitational wave emission in a time scale much shorter than the age of the universe. We estimate the density parameter of the resultant gravitational wave background. Astrophysical implication concerning the formation of intermediate-mass to supermassive black holes is also discussed.
Keywords
Cite
@article{arxiv.0909.1738,
title = {Rapid Merger of Binary Primordial Black Holes: an Implication for GW150914},
author = {Kimitake Hayasaki and Keitaro Takahashi and Yuuiti Sendouda and Shigehiro Nagataki},
journal= {arXiv preprint arXiv:0909.1738},
year = {2016}
}
Comments
7 pages, no figure. Accepted for publication in PASJ