It is known that the center-of-mass energy of the collision of two massive particles following
geodesics around a black hole presents a maximum. The maximum energy increases when …

We analyze the collisional Penrose process of spinning test particles in an extreme Kerr
black hole. We consider that two particles plunge into the black hole from infinity and collide …

The collisional Penrose process of charged spinning particles (charged tops) near the black
hole/white hole horizon (black hole and white hole horizon) for the metric of an extreme Kerr …

The collisional Penrose process received much attention when Bañados, Silk, and West
(BSW) pointed out the possibility of test-particle collisions with arbitrarily high center-of-mass …

The energy extraction of the collisional Penrose process has been investigated in recent
years. Previous researchers mainly concentrated on the case of nonspin massive or …

We consider the collision of two particles that move in the equatorial plane near a general
stationary rotating axially symmetric extremal black hole. One of the particles is critical (with …

We analyze the collisional Penrose process between a particle on the innermost stable
circular orbit (ISCO) orbit around an extreme Kerr black hole and a particle impinging from …

We consider a head-on collision of two massive particles that move in the equatorial plane
of an extremal Kerr black hole, which results in the production of two massless particles …

We consider a particle collision with a high center-of-mass energy near a Bañados-
Teitelboim-Zanelli (BTZ) black hole. We obtain the center-of-mass energy of two general …

High-energy collisions can occur for radially moving charged test particles in the extremal
Reissner-Nordström spacetime if one of the particles is fine-tuned and the collision point is …