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Could the 2.6 $M_odot$ object in GW190814 be a primordial black hole?

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 نشر من قبل Kyriakos Vattis
 تاريخ النشر 2020
  مجال البحث فيزياء
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On June 20, 2020, the LIGO-Virgo collaboration announced the discovery of GW190814, a gravitational wave event originating from a binary system merger between a black hole of mass $M_1 = 23.2^{+1.1} _ {-1.0}M_odot$ and an unidentified object with a mass of $M_2 = 2.59^{+0.08} _ {-0.09}M_odot$. This second object would be either the heaviest neutron star or lightest black hole observed to date. Here we investigate the possibility of the $sim 2.6M_odot$ object being a primordial black hole (PBH). We find that a primordial black hole explanation to GW190814 is unlikely as it is limited by the formation rate of the primary stellar progenitor and the observed merger rates of $mathcal{O}(20)M_odot$ massive black hole pairs.



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