Particle collisions and optical effects in the mining Kerr--Newman spacetimes

TL;DR

This paper investigates ultra-high-energy particle collisions and optical phenomena in mining Kerr-Newman naked singularity spacetimes, revealing unique collision energies and optical effects not present in black hole spacetimes.

Contribution

It introduces the concept of mining regimes in Kerr-Newman spacetimes, showing their potential for ultra-high-energy collisions and distinctive optical effects, differing from standard black hole scenarios.

Findings

Ultra-high-energy collisions occur with low-energy particles in mining regimes.

Observers can detect extremely blue-shifted radiation from the universe.

Mining regimes exhibit high efficiency of Keplerian accretion.

Abstract

We study ultra-high-energy particle collisions and optical effects in the extraordinary class of mining braneworld Kerr-Newman (KN) naked singularity spacetimes, predicting extremely high efficiency of Keplerian accretion, and compare the results to those related to the other classes of the KN naked singularity and black hole spacetimes. We demonstrate that in the mining KN spacetimes the ultra-high centre-of-mass energy occurs for collisions of particles following the extremely-low-energy stable circular geodesics of the \uvozovky{mining regime}, colliding with large family of incoming particles, e.g., those infalling from the marginally stable counter-rotating circular geodesics. This is qualitatively different situation in comparison to the standard KN naked singularity or black hole spacetimes where the collisional ultra-high centre-of-mass energy can be obtained only in the near-extreme spacetimes. We also show that observers following the stable circular geodesics of the mining regime can register extremely blue-shifted radiation incoming from the Universe, and see strongly deformed sky due to highly relativistic motion along such stable orbits. The strongly blue-shifted radiation could be thus a significant source of energy for such orbiting observers.