GW8 - Dense stellar environments as sites of gravitational wave emission |
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Speaker |
RASTELLO, SARA |
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Coauthors |
Arca-Sedda , Manuel; Capuzzo-Dolcetta , Roberto; Amaro-Seoane , Pau; Fragione , Giacomo; Tosta e Melo, Iara |
| Talk Title |
Stellar Black Hole Binary mergers in Open Clusters |
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Abstract |
I will present the results of our work on black hole binary (BHB) mergers in low dense star cluster. We perform a suite of direct-summation N−body simulations of small-and intermediate-size open clusters. These clusters host BHBs with masses in the range of the first LIGO/Virgo detections. For some of our models the binaries become very hard. Some of them are retained in the cluster and merge there, while ejected binaries typically have associated merger timescales which are too long. We find that perturbing stars around BHB systems are key to their coalescence, which would exceed a Hubble time if they were isolated. Those which merge in the cluster can be detected with an elapsed time of a few years with both ground-based detectors and space-borne ones, such as LISA, because they have a relatively high eccentricity. We estimate the BHB merger rate to be of R_mrg ∼ 2 yr^ −1 Gpc^ −3 . |
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Talk view |
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