Formation of binary black holes similar to GW190521 with a total mass of ∼150 M⊙ from Population III binary star evolution

Abstract

In case of zero metal (population III) stars, we show that total mass of binary black holes from binary population III star evolution can be $\sim 150 \,M_{\odot}$, which agrees with mass of a binary black hole, GW190521 recently discovered by LIGO/Virgo. The event rate of such binary black hole mergers is estimated as 0.13--0.66$~{\rm yr^{-1}~Gpc^{-3}}$, which is consistent with the observed value of 0.02--0.43$~{\rm yr^{-1}~Gpc^{-3}}$.