TY - JOUR

T1 - Hypercritical accretion during common envelopes in triples leading to binary black holes in the pair-instability-supernova mass gap

AU - Mendez, Enrique Moreno

AU - De Colle, Fabio

AU - Lopez-Camara, Diego

AU - Vigna-Gomez, Alejandro

PY - 2023/4/21

Y1 - 2023/4/21

N2 - Hydrodynamic studies of stellar-mass compact objects (COs) in a common envelope (CE) have shown that the accretion rate onto the CO is a few orders of magnitude below the Bondi-Hoyle-Lyttleton (BHL) estimate. This is several orders of magnitude above the Eddington limit and above the limit for neutrino-cooled accretion (i.e. hypercritical accretion or HCA). Considering that a binary system inside the CE of a third star accretes material at nearly the same rate as a single object of the same total mass, we propose stellar-evolution channels which form binary black hole (BBH) systems with its component masses within the pair-instability supernova (PISN) mass gap. Our model is based on HCA onto the BBH system engulfed into the CE of a massive tertiary star. Furthermore, we propose a mass transfer mode which allows to store mass lost by the binary onto a third star. Through the use of population synthesis simulations for the evolution of BBHs and standard binary-evolution principles for the interaction with a tertiary star, we are able to produce BBHs masses consistent with those estimated for GW190521. We also discuss the massive binary system Mk34 as a possible progenitor of BBHs in the PISN gap.

AB - Hydrodynamic studies of stellar-mass compact objects (COs) in a common envelope (CE) have shown that the accretion rate onto the CO is a few orders of magnitude below the Bondi-Hoyle-Lyttleton (BHL) estimate. This is several orders of magnitude above the Eddington limit and above the limit for neutrino-cooled accretion (i.e. hypercritical accretion or HCA). Considering that a binary system inside the CE of a third star accretes material at nearly the same rate as a single object of the same total mass, we propose stellar-evolution channels which form binary black hole (BBH) systems with its component masses within the pair-instability supernova (PISN) mass gap. Our model is based on HCA onto the BBH system engulfed into the CE of a massive tertiary star. Furthermore, we propose a mass transfer mode which allows to store mass lost by the binary onto a third star. Through the use of population synthesis simulations for the evolution of BBHs and standard binary-evolution principles for the interaction with a tertiary star, we are able to produce BBHs masses consistent with those estimated for GW190521. We also discuss the massive binary system Mk34 as a possible progenitor of BBHs in the PISN gap.

KW - Accretion

KW - accretion discs

KW - stars: massive

KW - stars: black holes

KW - transients: black hole mergers

KW - stars: evolution

KW - DYNAMICAL FORMATION

KW - EVOLUTION

KW - STARS

KW - MERGER

KW - GROWTH

KW - SCENARIO

KW - PERTURBATIONS

KW - SIMULATIONS

KW - INCLINATION

KW - RADIATION

U2 - 10.1093/mnras/stad1082

DO - 10.1093/mnras/stad1082

M3 - Journal article

VL - 522

SP - 1686

EP - 1696

JO - Royal Astronomical Society. Monthly Notices

JF - Royal Astronomical Society. Monthly Notices

SN - 0035-8711

IS - 2

ER -