2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/203096It is shown how high energy neutrino beams from very distant sources can be utilized to learn about many properties of neutrinos such as lifetimes, mass hierarchy, mixing, minuscule pseudo-Dirac mass splittings; in addition, the production mechanism of neutrinos in astrophysical sources can also be elucidated.22 pages. Presented at the COSPA 2007, Taipei, November 2007; to be published in the proceedings. Added referencesHigh Energy Physics - PhenomenologyAstrophysicsHigh Energy Physics - Experimenttext