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arXiv · 1810.09257

Formation Redshift of the Massive Black Holes Detected by LIGO

Razieh Emami·Abraham Loeb
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Abstract

We compare the event rate density detected by LIGO to the comoving number density of isolated stellar progenitors and find a range for their formation redshift. Our limit depends on the threshold mass for making the black holes (BHs) but only weakly on the metallicity of their progenitor. If $10 \%$ of all BHs are in coalescing binaries, then enough progenitors have formed by $ 2< z_f < 9 $.

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Razieh Emami, Abraham Loeb. 2018-10-19. Formation Redshift of the Massive Black Holes Detected by LIGO. https://arxiv.org/abs/1810.09257

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