Detectability of stochastic gravitational wave background from weakly hyperbolic encounters

0585713 - ASÚ 2025 RIV FR eng J - Journal Article
Kerachian, Morteza - Mukherjee, Sajal - Lukes-Gerakopoulos, Georgios - Mitra, S.
Detectability of stochastic gravitational wave background from weakly hyperbolic encounters.
Astronomy & Astrophysics. Roč. 684, April (2024), č. článku A17. ISSN 0004-6361. E-ISSN 1432-0746
Grant - others:AV ČR(CZ) LQ100032102
Program: Prémie Lumina quaeruntur
Institutional support: RVO:67985815
Keywords : black hole physics * gravitational waves * scattering
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 6.5, year: 2022
Method of publishing: Open access

We compute the stochastic gravitational wave (GW) background generated by black hole-black hole (BH-BH) hyperbolic encounters with eccentricities close to one and compare them with the respective sensitivity curves of planned GW detectors. We use the Keplerian potential to model the orbits of the encounters and the quadrupole formula to compute the emitted GWs. We take into account hyperbolic encounters that take place in clusters up to redshift 5 and with BH masses spanning from 5 M-circle dot to 55 M-circle dot. We assume the clusters to be virialized and study several cluster models with different mass and virial velocity, and finally obtain an accumulative result, displaying the background as an average. Using the maxima and minima of our accumulative result for each frequency, we provide analytical expressions for both optimistic and pessimistic scenarios. Our results suggest that the background from these encounters is likely to be detected by the third-generation detectors Cosmic explorer and Einstein telescope, while the tail section at lower frequencies intersects with DECIGO, making it a potential target source for both ground- and space-based future GW detectors.
Permanent Link: https://hdl.handle.net/11104/0353907