Extreme-mass-ratio-bursts from extragalactic sources

Berry, C. P. L. and Gair, J.R. (2013) Extreme-mass-ratio-bursts from extragalactic sources. Monthly Notices of the Royal Astronomical Society, 433(4), pp. 3572-3583. (doi: 10.1093/mnras/stt990)

Abstract

Extreme-mass-ratio bursts (EMRBs) are a class of potentially interesting gravitational wave signals. They are produced when a compact object passes through periapsis on a highly eccentric orbit about a much more massive object; we consider stellar mass objects orbiting the massive black holes (MBHs) found in galactic centres. Such a system may emit many EMRBs before eventually completing the inspiral. There are several nearby galaxies that could yield detectable bursts. For a space-borne interferometer like the Laser Interferometer Space Antenna, sensitivity is greatest for EMRBs from MBHs of ∼106–107 M⊙, which could be detected out to ∼100 Mpc. Considering the examples of M32, NGC 4945 and NGC 4395 we investigate if extragalactic EMRB signals can provide information about their sources. This is possible, but only if the periapse radius of the orbit is small, of the order of rp ≲ 8rg, where rg = GM c− 2 is the gravitational radius of the MBH. This limits the utility of EMRBs as an astronomical tool. However, if we are lucky, we could place constraints on the mass and spin of nearby MBHs with 1 per cent precision.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Berry, Dr Christopher
• Authors: Berry, C. P. L., and Gair, J.R.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Monthly Notices of the Royal Astronomical Society
• Publisher: Oxford University Press
• ISSN: 0035-8711
• ISSN (Online): 1365-2966
• Published Online: 24 June 2013
• Copyright Holders: Copyright © 2013 The Authors
• First Published: First published in Monthly Notices of the Royal Astronomical Society 433(4): 3572-3583
• Publisher Policy: Reproduced under a Creative Commons License