Estimating Hawking radiation for exotic black holes

TL;DR

This paper proposes an approximation method for Hawking radiation in exotic black holes, analyzing scalar fields in specific models and showing that the radiation can be approximated by black body radiation with a temperature estimated at a critical impact parameter.

Contribution

It introduces an approximation technique for Hawking radiation applicable to exotic black holes with peculiar thermodynamic properties.

Findings

Hawking radiation can be approximated by black body radiation in these models.

The approximation works well except for extreme black holes.

Hawking temperature can be estimated at a critical impact parameter.

Abstract

We study about an approximation method of the Hawking radiation. We analyze an massless scalar field in exotic black hole backgrounds models which have peculiar properties in black hole thermodynamics (monopole black hole in SO(3) Einstein-Yang-Mills-Higgs system and dilatoic black hole in Einstein-Maxwell-dilaton system). A scalar field is assumed not to be couple to matter fields consisting of a black hole background. Except for extreme black holes, we can well approximate the Hawking radiaition by `black body' one with Hawking temperature estimated at a radius of a critical impact parameter.