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arXiv · 2007.10896

Observational manifestations of "cosmological dinosaurs'' at redshifts $z\sim20$

V. K. Dubrovich·Yu. N. Eroshenko·S. I. Grachev
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Abstract

We consider a primordial black hole of very high mass, $10^9-10^{10}M_\odot$, surrounded by dark matter and barionic halo at redshifts $z\sim20$ without any local sources of energy release. Such heavy and concentrated objects in the early universe were previously called ``cosmological dinosaurs''. Spectral distribution and spatial variation of the brightness in the 21 cm line of atomic hydrogen are calculated with the theory of radiation transfer. It is shown that a narrow and deep absorption arises in the form of the spherical shell around the primordial black hole at the certain radius. The parameters of this shell depend almost exclusively on the mass of the black hole. The hardware and methodological aspects of the search for such objects are discussed.

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V. K. Dubrovich, Yu. N. Eroshenko, S. I. Grachev. 2020-07-21. Observational manifestations of "cosmological dinosaurs'' at redshifts $z\sim20$. https://doi.org/10.1093/mnras%2Fstab689

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