Scalar Synchrotron Radiation in the Schwarzschild-anti-de Sitter Geometry

TL;DR

This paper analyzes scalar radiation emitted by particles in circular orbits around Schwarzschild-anti-de Sitter black holes, revealing a transition in radiation patterns depending on black hole size, which differs from flat spacetime behavior.

Contribution

It provides a complete relativistic analysis of scalar synchrotron radiation in Schwarzschild-AdS geometry, highlighting a novel transition in radiation multipolar distribution based on black hole size.

Findings

Large black holes produce high multipolar, narrowly focused radiation.

Small black holes emit low multipolar, more isotropic radiation.

A transition mass at M=0.427 R separates different radiation behaviors.

Abstract

We present a complete relativistic analysis for the scalar radiation emitted by a particle in circular orbit around a Schwarzschild-anti-de Sitter black hole. If the black hole is large, then the radiation is concentrated in narrow angles- high multipolar distribution- i.e., the radiation is synchrotronic. However, small black holes exhibit a totally different behavior: in the small black hole regime, the radiation is concentrated in low multipoles. There is a transition mass at $M=0.427 R$, where $R$ is the AdS radius. This behavior is new, it is not present in asymptotically flat spacetimes.