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arXiv · 1804.06624

Through a Mini Halo, Darkly

Geoff Beck·Sergio Colafrancesco
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Abstract

In this Letter we explore the effects of the scattering of photons incident on a dark matter halo through their interaction with either electrons or photons produced by dark matter annihilation. Particularly, we examine the effects of this scattering upon the observed spectrum of a distant AGN or of the Cosmic Microwave Background. Our results indicate that ultra-compact mini halos and other dense dark matter clumps can induce an observable Comptonisation of AGN spectra as well as a Sunyaev-Zel'dovich effect (SZE) with an optical depth similar to that attained by thermal electrons in the Coma cluster. The rate of encounters between a distant AGN and these dense mini-halos is also estimated using micro-lensing limits existing on the population of dark compact bodies.

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Geoff Beck, Sergio Colafrancesco. 2019-01-23. Through a Mini Halo, Darkly. https://doi.org/10.1093/mnras%2Fstz318

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