English

Waves from the Centre: Probing PBH and other Macroscopic Dark Matter with LISA

General Relativity and Quantum Cosmology 2020-10-23 v2 Cosmology and Nongalactic Astrophysics

Abstract

A significant fraction of cosmological dark matter can be formed by very dense macroscopic objects, for example primordial black holes. Gravitational waves offer a promising way to probe these kinds of dark-matter candidates, in a parameter space region that is relatively untested by electromagnetic observations. In this work we consider an ensemble of macroscopic dark matter with masses in the range 101310^{-13} - 1M1\,M_{\odot} orbiting a super-massive black hole. While the strain produced by an individual dark-matter particle will be very small, gravitational waves emitted by a large number of such objects will add incoherently and produce a stochastic gravitational-wave background. We show that LISA can be a formidable machine for detecting the stochastic background of such objects orbiting the black hole in the centre of the Milky Way, Sgr\.A ⁣{\rm A}^{\!*}, if a dark-matter spike of the type originally predicted by Gondolo and Silk forms near the central black hole.

Keywords

Cite

@article{arxiv.1811.06387,
  title  = {Waves from the Centre: Probing PBH and other Macroscopic Dark Matter with LISA},
  author = {Florian Kuhnel and Andrew Matas and Glenn D. Starkman and Katherine Freese},
  journal= {arXiv preprint arXiv:1811.06387},
  year   = {2020}
}

Comments

v2: Update to match published version. arXiv admin note: text overlap with arXiv:1705.10361