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

C. P. L. Berry; J. R. Gair

doi:10.1093/mnras/stt1543

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arXiv · 1307.7276

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

C. P. L. Berry·J. R. Gair

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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.

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C. P. L. Berry, J. R. Gair. 2013-07-27. Expectations for extreme-mass-ratio bursts from the Galactic Centre. https://doi.org/10.1093/mnras/stt1543

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