2005/09/22 by V. Berezinsky
Physics and Astronomy · #astro-ph
published as Proc. of 11th Int. Workshop NEUTRINO TELESCOPES (ed. Milla Baldo Ceolin) p. 339, 2005 · 16 pages, 6 figures
arxiv created 2005/09/22 · arxiv updated 2009/12/01
The sources and fluxes of superGZK neutrinos, E>1020 eV, are discussed. The fluxes of \em cosmogenic neutrinos, i.e. those produced by ultra-high energy cosmic rays (UHECR) interacting with CMB photons, are calculated in the models, which give the good fit to the observed flux of UHECR. The best fit given in no-evolutionary model with maximum acceleration energy E\rm max=1× 1021 eV results in very low flux of superGZK neutrinos an order of magnitude lower than the observed flux of UHECR. The predicted neutrino flux becomes larger and observable by next generation detectors at energies 1020 - 1021 eV in the evolutionary models with E\rm max=1× 1023 eV. The largest cosmogenic neutrino flux is given in models with very flat generation spectrum, e.g. ∝ E-2. The neutrino energies are naturally high in the models of \em superheavy dark matter and topological defects. Their fluxes can also be higher than those of cosmogenic neutrinos. The largest fluxes are given by \em mirror neutrinos, oscillating into ordinary neutrinos. Their fluxes obey some theoretical upper limit which is very weak, and in practice these fluxes are most efficiently limited now by observations of radio emission from neutrino-induced showers.