Radiation Spectra and Effective Temperatures in Higher-Dimensional Charged-de Sitter Black Holes

TL;DR

This paper investigates the radiation spectra and effective temperatures of higher-dimensional charged-de Sitter black holes, analyzing scalar field emissions, various temperature definitions, and the impact of coupling parameters on energy emission rates.

Contribution

It introduces a comprehensive analysis of multiple temperature definitions and their effects on scalar field emissions in higher-dimensional black holes, including bulk and brane channels.

Findings

Bousso-Hawking temperature yields dominant energy emission.

Coupling parameters suppress emission rates.

Bulk emission can dominate over brane emission under certain conditions.

Abstract

In this study, a scalar field propagating in a higher-dimensional Reissner-Nordstr\"om-de Sitter black hole is investigated. Scalar fields are assumed to have non-minimal coupling to the brane or bulk scalar curvature. Five different {definitions} of black hole temperatures are discussed: temperature based on surface gravity, Bousso-Hawking temperature, and three effective temperatures. The greybody factors of minimally and non-minimally coupled scalar fields on the brane and in the bulk are examined under the effect of particle and spacetime properties. The energy emission spectra of black holes are determined at various temperatures for both the brane and bulk channels. The energy emission rates at the Bousso-Hawking temperature are found to be dominant over those at other temperatures. The energy emission curves are suppressed by the presence of coupling parameters. Finally, the bulk-over-brane emission ratios are calculated. Notably, bulk dominance becomes possible for a certain definition of the temperatures and regime of the cosmological constant.