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arXiv · 1612.06811

CMB constraints on primordial black hole dark matter

Daniel Aloni·Kfir Blum·Raphael Flauger
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Abstract

We revisit cosmic microwave background (CMB) constraints on primordial black hole dark matter. Spectral distortion limits from COBE/FIRAS do not impose a relevant constraint. Planck CMB anisotropy power spectra imply that primordial black holes with $m_{BH}\gtrsim 5~M_{\odot}$ are disfavored. However, this is susceptible to sizeable uncertainties due to the treatment of the black hole accretion process. These constraints are weaker than those quoted in earlier literature for the same observables.

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Daniel Aloni, Kfir Blum, Raphael Flauger. 2016-12-20. CMB constraints on primordial black hole dark matter. https://doi.org/10.1088/1475-7516%2F2017%2F05%2F017

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