A Triple Scenario for the Formation of Wide Black Hole Binaries Such As Gaia BH1

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Generozov, A., Perets, H. B.
Formato: Preprint
Publicado: 2023
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866909586943901696
author Generozov, A.
Perets, H. B.
author_facet Generozov, A.
Perets, H. B.
contents Recently, several non-interacting black hole-stellar binaries have been identified in Gaia data. For example, Gaia BH1, where a Sun-like star is in a moderate eccentricity (e=0.44), 185-day orbit around a black hole. This orbit is difficult to explain through binary evolution. The present-day separation suggests the progenitor system would have undergone an episode of common envelope evolution, but a common envelope should shrink the period below the observed one. Since the majority of massive stars form in higher multiplicity systems, a triple evolution scenario is more likely for the progenitors of BH binaries. Here we show that such systems can indeed be more easily explained via evolution in hierarchical triple systems. von Zeipel-Lidov-Kozai oscillations or instabilities can delay the onset of the common envelope phase in the inner binary of the triple, so that the black hole progenitor and low-mass star are more widely separated when it begins, leading to the formation of wider binaries. There are also systems with similar periods but larger eccentricities, where the BH progenitor is a merger product of the inner binary in the triple. Such mergers lead to a more top-heavy black hole mass function.
format Preprint
id arxiv_https___arxiv_org_abs_2312_03066
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle A Triple Scenario for the Formation of Wide Black Hole Binaries Such As Gaia BH1
Generozov, A.
Perets, H. B.
Solar and Stellar Astrophysics
Astrophysics of Galaxies
High Energy Astrophysical Phenomena
Recently, several non-interacting black hole-stellar binaries have been identified in Gaia data. For example, Gaia BH1, where a Sun-like star is in a moderate eccentricity (e=0.44), 185-day orbit around a black hole. This orbit is difficult to explain through binary evolution. The present-day separation suggests the progenitor system would have undergone an episode of common envelope evolution, but a common envelope should shrink the period below the observed one. Since the majority of massive stars form in higher multiplicity systems, a triple evolution scenario is more likely for the progenitors of BH binaries. Here we show that such systems can indeed be more easily explained via evolution in hierarchical triple systems. von Zeipel-Lidov-Kozai oscillations or instabilities can delay the onset of the common envelope phase in the inner binary of the triple, so that the black hole progenitor and low-mass star are more widely separated when it begins, leading to the formation of wider binaries. There are also systems with similar periods but larger eccentricities, where the BH progenitor is a merger product of the inner binary in the triple. Such mergers lead to a more top-heavy black hole mass function.
title A Triple Scenario for the Formation of Wide Black Hole Binaries Such As Gaia BH1
topic Solar and Stellar Astrophysics
Astrophysics of Galaxies
High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2312.03066