The dragon-II simulations

• Verfasst von: Arca Sedda, Manuel [VerfasserIn]
• Verfasst von: Kamlah, Albrecht [VerfasserIn]
• Verfasst von: Spurzem, Rainer [VerfasserIn]
• Verfasst von: Rizzuto, Francesco Paolo [VerfasserIn]
• Verfasst von: Giersz, Mirek [VerfasserIn]
• Verfasst von: Naab, Thorsten [VerfasserIn]
• Verfasst von: Berczik, Peter [VerfasserIn]
• Titel: The dragon-II simulations
• Titelzusatz: III. Compact binary mergers in clusters with up to 1 million stars : mass, spin, eccentricity, merger rate, and pair instability supernovae rate
• Verf.angabe: Manuel Arca sedda, Albrecht W H Kamlah, Rainer Spurzem, Francesco Paolo Rizzuto, Mirek Giersz, Thorsten Naab and Peter Berczik
• E-Jahr: 2024
• Jahr: March 2024
• Umfang: 20 S.
• Illustrationen: Illustrationen
• Fussnoten: Vorab online veröffentlicht: 2024 January 9 ; Gesehen am 03.07.2024
• Titel Quelle: Enthalten in: Royal Astronomical SocietyMonthly notices of the Royal Astronomical Society
• Ort Quelle: Oxford : Oxford Univ. Press, 1827
• Jahr Quelle: 2024
• Band/Heft Quelle: 528(2024), 3 vom: März, Seite 5140-5159
• ISSN Quelle: 1365-2966
• DOI: doi:10.1093/mnras/stad3951
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1893560473

Abstract

Compact binary mergers forming in star clusters may exhibit distinctive features that can be used to identify them among observed gravitational-wave sources. Such features likely depend on the host cluster structure and the physics of massive star evolution. Here, we dissect the population of compact binary mergers in the dragon-II simulation data base, a suite of 19 direct N-body models representing dense star clusters with up to 106 stars and < 33 per cent of stars in primordial binaries. We find a substantial population of black hole binary (BBH) mergers, some of them involving an intermediate-mass BH (IMBH), and a handful mergers involving a stellar BH and either a neutron star (NS) or a white dwarf (WD). Primordial binary mergers, ~ 30 cent of the whole population, dominate ejected mergers. Dynamical mergers, instead, dominate the population of in-cluster mergers and are systematically heavier than primordial ones. Around 20 per cent of dragon-II mergers are eccentric in the Laser Interferometer Space Antenna (LISA) band and 5 per cent in the LIGO band. We infer a mean cosmic merger rate of R ∼ 30(4.4)(1.2) yr−1 Gpc−3 for BBHs, NS–BH, and WD–BH binary mergers, respectively, and discuss the prospects for multimessenger detection of WD-BH binaries with LISA. We model the rate of pair-instability supernovae (PISNe) in star clusters and find that surveys with a limiting magnitude mbol = 25 can detect ∼1-15 yr−1 PISNe. Comparing these estimates with future observations could help to pin down the impact of massive star evolution on the mass spectrum of compact stellar objects in star clusters.