2003/07/07 by S. Kovesi-Domokos, Kovesi-Domokos, S., G. Domokos +1
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/0307098
Presented by S. Kovesi-Domokos at the Jophns Hopkins Workshop, "High Eenergy Reactions", Heidelberg 2002
arxiv created 2003/07/07 · arxiv updated 2009/12/01
Ultra high energy cosmic rays (UHECR) pose a problem either for particle physics or for astrophysics (or for both) by the unexpectedly high number of cosmic ray showers observed with energy above about 5x1019eV, the Greisen-Zatsepin-Kuzmin (GZK) cutoff. Our emphasis is on those possible solutions of the puzzle which assume that ultra high energy neutrinos travel cosmic distances. We present, in detail, a model which is based on a low energy (50 to 100 TeV) transition to a higher than four dimensional string regime. Neutrino-quark cross sections grow exponentially close to the threshold of this new scale because of the fast increase of the density of string states and effectively acquire hadronic strength.