Ultrahigh Energy Cosmic Rays: New Physics or Old Physics?
arXiv:astro-ph/0407311 · doi:10.1016/j.nuclphysbps.2004.10.028
Abstract
We consider the advantages of and the problems associated with hypotheses to explain the origin of ulthrahigh energy cosmic rays (UHECR: E > 10 EeV) and the "trans GZK" cosmic rays (TGZK: E > 100 EeV), both through "old physics" (acceleration in cosmic sources) and "new physics" (new particles, topological defects, fat neutrino cross sections, Lorentz invariance violation).
Invited paper for CRIS 2004 Intl. Seminar on Cosmic Rays: "GZK and Surroundings", to be published in Nucl. Phys. B