English

Expectations for extreme-mass-ratio bursts from the Galactic Centre

High Energy Astrophysical Phenomena 2013-10-15 v3 General Relativity and Quantum Cosmology

Abstract

When a compact object on a highly eccentric orbit about a much more massive body passes through periapsis it emits a short gravitational wave signal known as an extreme-mass-ratio burst (EMRB). We consider stellar mass objects orbiting the massive black hole (MBH) found in the Galactic Centre. EMRBs provide a novel means of extracting information about the MBH; an EMRB from the Galactic MBH could be highly informative regarding the MBH's mass and spin if the orbital periapsis is small enough. However, to be a useful astronomical tool EMRBs must be both informative and sufficiently common to be detectable with a space-based interferometer. We construct a simple model to predict the event rate for Galactic EMRBs. We estimate there could be on average ~2 bursts in a two year mission lifetime for LISA. Stellar mass black holes dominate the event rate. Creating a sample of 100 mission realisations, we calculate what we could learn about the MBH. On average, we expect to be able to determine the MBH mass to ~1% and the spin to ~0.1 using EMRBs.

Keywords

Cite

@article{arxiv.1307.7276,
  title  = {Expectations for extreme-mass-ratio bursts from the Galactic Centre},
  author = {C. P. L. Berry and J. R. Gair},
  journal= {arXiv preprint arXiv:1307.7276},
  year   = {2013}
}

Comments

22 pages, 5 figures, 2 appendices. Minor changes to reflect published version

R2 v1 2026-06-22T00:58:54.635Z