Non-thermal Production of Dark Matter from Primordial Black Holes

TL;DR

This paper proposes a novel non-thermal dark matter production mechanism via primordial black hole evaporation, requiring an enhanced small-scale power spectrum, and successfully explains dark matter abundance for particles in the 100 GeV-10 TeV range.

Contribution

It introduces a new scenario where primordial black holes formed during early matter domination produce dark matter through evaporation, linking small-scale power spectrum enhancement to dark matter relic abundance.

Findings

Primordial black hole evaporation can account for all dark matter.

Correct relic abundance achieved for dark matter masses 100 GeV-10 TeV.

Small-scale power spectrum must be enhanced by about 10^5.

Abstract

We present a scenario for non-thermal production of dark matter from evaporation of primordial black holes. A period of very early matter domination leads to formation of black holes with a maximum mass of $\simeq 2 \times 10^8$ g, whose subsequent evaporation prior to big bang nucleosynthesis can produce all of the dark matter in the universe. We show that the correct relic abundance can be obtained in this way for thermally underproduced dark matter in the 100 GeV-10 TeV mass range. To achieve this, the scalar power spectrum at small scales relevant for black hole formation should be enhanced by a factor of ${\cal O}(10^5)$ relative to the scales accessible by the cosmic microwave background experiments.