Acceleration of particles in Einstein-Maxwell-dilaton black holes

TL;DR

This paper investigates particle collisions near various Einstein-Maxwell-dilaton black holes, demonstrating that the energy of such collisions can become arbitrarily high at the horizon in several black hole and naked singularity scenarios.

Contribution

It extends the analysis of particle acceleration to Einstein-Maxwell-dilaton black holes, including charged, rotating, and naked singularity cases, showing unbounded collision energies.

Findings

Center-of-mass energy is unlimited at the horizon for certain black holes.

Unbounded energy occurs in both extremal and near-extremal cases.

Naked singularities also exhibit infinite collision energies.

Abstract

It has recently been pointed out that, under certain conditions, the energy of particles accelerated by black holes in the center-of-mass frame can become arbitrarily high. In this paper, we study the collision of two particles in the case of four-dimensional charged nonrotating, extremal charged rotating and near-extremal charged rotating Kaluza-Klein black holes as well as the naked singularity case in Einstein-Maxwell-dilaton theory. We find that the center-of-mass energy for a pair of colliding particles is unlimited at the horizon of charged nonrotating Kaluza-Klein black holes, extremal charged rotating Kaluza-Klein black holes and in the naked singularity case.