High-energy astrophysics with neutrino telescopes

Neutrino astrophysics offers new perspectives on the Universe investigation: high-energy neutrinos, produced by the most energetic phenomena in our Galaxy and in the Universe, carry complementary (if not exclusive) information about the cosmos with respect to photons. While the small interaction cross section of neutrinos allows them to come from the core of astrophysical objects, it is also a drawback, as their detection requires a large target mass. This is why it is convenient to put huge cosmic neutrino detectors in natural locations, like deep underwater or under-ice sites. In order to supply for such extremely hostile environmental conditions, new frontier technologies are under development. The aim of this work is to review the motivations for high-energy neutrino astrophysics, the present status of experimental results and the technologies used in underwater/ice Cherenkov experiments, with a special focus on the efforts for the construction of a km3-scale detector in the Mediterranean Sea.