Extreme mass ratio inspirals (EMRIs) are compact binary systems characterized by a mass ratio q = m/M in the range 10−9–10−4 and represent primary gravitational wave (GW) sources for the forthcoming Laser Interferometer Space Antenna (LISA). While their standard formation channel involves relaxation processes deflecting compact objects on very low angular momentum orbits around the central massive black hole, a number of alternative formation channels has been proposed, including binary tidal break-up, migration in accretion discs and secular and chaotic dynamics around a massive black hole binary (MBHB). In this work, we take an extensive closer look at this latter scenario, investigating how EMRIs can be triggered by MBHBs, formed in the aftermath of galaxy mergers. By employing a suite of relativistic three-body simulations, we evaluate the efficiency of EMRI formation for different parameters of the MBHB, assessing the importance of both secular and chaotic dynamics. By modelling the distribution of compact objects in galaxy nuclei, we estimate the resulting EMRI formation rate, finding that EMRI are produced in a sharp burst, with peak rates that are 10–100 times higher than the standard two-body relaxation channel, lasting for 106–108 yr. By coupling our results with an estimate of the cosmic MBHB merger rate, we finally forecast that LISA could observe O(10) EMRIs per year formed by this channel.

Mazzolari, G., Bonetti, M., Sesana, A., Colombo, R., Dotti, M., Lodato, G., et al. (2022). Extreme mass ratio inspirals triggered by massive black hole binaries: from relativistic dynamics to cosmological rates. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 516(2 (October 2022)), 1959-1976 [10.1093/mnras/stac2255].

Extreme mass ratio inspirals triggered by massive black hole binaries: from relativistic dynamics to cosmological rates

Bonetti, M
Secondo
;
Sesana, A;Dotti, M;Izquierdo-Villalba, D
2022

Abstract

Extreme mass ratio inspirals (EMRIs) are compact binary systems characterized by a mass ratio q = m/M in the range 10−9–10−4 and represent primary gravitational wave (GW) sources for the forthcoming Laser Interferometer Space Antenna (LISA). While their standard formation channel involves relaxation processes deflecting compact objects on very low angular momentum orbits around the central massive black hole, a number of alternative formation channels has been proposed, including binary tidal break-up, migration in accretion discs and secular and chaotic dynamics around a massive black hole binary (MBHB). In this work, we take an extensive closer look at this latter scenario, investigating how EMRIs can be triggered by MBHBs, formed in the aftermath of galaxy mergers. By employing a suite of relativistic three-body simulations, we evaluate the efficiency of EMRI formation for different parameters of the MBHB, assessing the importance of both secular and chaotic dynamics. By modelling the distribution of compact objects in galaxy nuclei, we estimate the resulting EMRI formation rate, finding that EMRI are produced in a sharp burst, with peak rates that are 10–100 times higher than the standard two-body relaxation channel, lasting for 106–108 yr. By coupling our results with an estimate of the cosmic MBHB merger rate, we finally forecast that LISA could observe O(10) EMRIs per year formed by this channel.
Articolo in rivista - Articolo scientifico
black hole physics; celestial mechanics; gravitational waves; methods: numerical;
English
17-ago-2022
2022
516
2 (October 2022)
1959
1976
none
Mazzolari, G., Bonetti, M., Sesana, A., Colombo, R., Dotti, M., Lodato, G., et al. (2022). Extreme mass ratio inspirals triggered by massive black hole binaries: from relativistic dynamics to cosmological rates. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 516(2 (October 2022)), 1959-1976 [10.1093/mnras/stac2255].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/393012
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