Low energy Greybody factors for fermions emitted by a Schwarzschild-de Sitter black hole

TL;DR

This paper analytically investigates low-energy greybody factors for fermions emitted by Schwarzschild-de Sitter black holes, revealing constant factors at low energies and an enhancement with increasing cosmological constant, aligning with previous numerical results.

Contribution

It provides an analytical approach to compute low-energy fermionic greybody factors for Schwarzschild-de Sitter black holes, extending previous scalar particle studies.

Findings

Greybody factors are constant at low energies for fixed angular momentum.

Energy spectrum is enhanced with higher cosmological constant.

Results agree with prior numerical calculations.

Abstract

In this paper we are discussing the problem of low-energy greybody factors for fermions emitted by a Schwarzschild-de Sitter black hole. In our study we are using the analytical methods proposed by Unruh some time ago for determining the greybody factors. We have found that at low energies the greybody factors are constant for a given total angular momentum (similar to what happens in the case of scalar particles reported before in the literature). Also our results are indicating an enhancement in the energy spectrum if one is increasing the value of the cosmological constant. These results are consistent with numerical calculations performed in Ref.[14] by S.F. Wu et al. (Phys.Rev.D 78, 084010).