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arXiv · 2407.16373

Primordial Intermediate-mass Binary Black Holes as Targets for Space Laser Interferometers

Konstantin Postnov·Ilya Chekh
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Abstract

Primordial black holes (PBHs) with log-normal mass spectrum with masses up to $\sim 10^4-10^5 M_\odot$ can be created after QCD phase transition in the early Universe at $z\sim 10^{12}$ by the modified Affleck-Dine baryogenesis. Using a model binary PBH formation, the expected detection rate of such binary intermediate-mass PBHs by the TianQin space laser interferometer is calculated to be from a few to hundreds events per year for the assumed parameters of the PBH log-normal mass spectrum and abundance consistent with LIGO-Virgo-KAGRA results. Distinctive features of such primordial IMBH mergings are vanishingly small effective spins, possible high redshifts $z>20$ and lack of association with gas-rich regions or galaxies.

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Konstantin Postnov, Ilya Chekh. 2024-07-23. Primordial Intermediate-mass Binary Black Holes as Targets for Space Laser Interferometers. https://arxiv.org/abs/2407.16373

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