000118210 001__ 118210
000118210 005__ 20240319081021.0
000118210 0247_ $$2doi$$a10.1088/1475-7516/2022/05/023
000118210 0248_ $$2sideral$$a129606
000118210 037__ $$aART-2022-129606
000118210 041__ $$aeng
000118210 100__ $$aLiberati, S.
000118210 245__ $$aExploring black holes as particle accelerators: Hoop-radius, target particles and escaping conditions
000118210 260__ $$c2022
000118210 5060_ $$aAccess copy available to the general public$$fUnrestricted
000118210 5203_ $$aThe possibility that rotating black holes could be natural particle accelerators has been subject of intense debate. While it appears that for extremal Kerr black holes arbitrarily high center of mass energies could be achieved, several works pointed out that both theoretical as well as astrophysical arguments would severely dampen the attainable energies. In this work we study particle collisions near Kerr black holes, by reviewing and extending the so far proposed scenarios. Most noticeably, we shall focus on the recently advanced target particle scenarios which were claimed to reach arbitrarily high energies even for Schwarzschild black holes. By implementing the hoop conjecture we show that these scenarios involving near-horizon target particles are in principle able to attain, sub-Planckian, but still ultra-high center of mass energies of the order of 1023-1025 eV even for non-extremal Kerr black holes. Furthermore, analysing the properties of particles produced in such collisions, we find that photons can escape to infinity. However, their energy is only of the order of the energy of the colliding particles and hence relatively low, which is the same conclusion previously reached in the literature about the original Bañados-Silk-West process. This finding points towards a general limitation of collisional Penrose processes, at least for what concerns their primary products.
000118210 536__ $$9info:eu-repo/grantAgreement/ES/AEI/PID2019-106802GB-I00
000118210 540__ $$9info:eu-repo/semantics/openAccess$$aby-nc-nd$$uhttp://creativecommons.org/licenses/by-nc-nd/3.0/es/
000118210 590__ $$a6.3$$b2022
000118210 592__ $$a0.893$$b2022
000118210 591__ $$aPHYSICS, PARTICLES & FIELDS$$b5 / 29 = 0.172$$c2022$$dQ1$$eT1
000118210 593__ $$aAstronomy and Astrophysics$$c2022$$dQ2
000118210 591__ $$aASTRONOMY & ASTROPHYSICS$$b10 / 69 = 0.145$$c2022$$dQ1$$eT1
000118210 594__ $$a10.2$$b2022
000118210 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/acceptedVersion
000118210 700__ $$aPfeifer, C.
000118210 700__ $$0(orcid)0000-0003-1130-3982$$aRelancio Martínez, J.
000118210 773__ $$g2022, 5 (2022), 023 [17 pp]$$pJ. Cosmol. Astropart. Phys.$$tJournal of Cosmology and Astroparticle Physics$$x1475-7516
000118210 8564_ $$s524351$$uhttps://zaguan.unizar.es/record/118210/files/texto_completo.pdf$$yPostprint
000118210 8564_ $$s1711999$$uhttps://zaguan.unizar.es/record/118210/files/texto_completo.jpg?subformat=icon$$xicon$$yPostprint
000118210 909CO $$ooai:zaguan.unizar.es:118210$$particulos$$pdriver
000118210 951__ $$a2024-03-18-16:13:05
000118210 980__ $$aARTICLE