Dedicated Supernova Detection by a Network of Neutral Current Spherical TPC's

Supernova neutrinos can easily be detected by a spherical gaseous TPC detector measuring very low energy nuclear recoils. The expected rates are quite large for a neutron rich target since the neutrino nucleus neutral current interaction yields a coherent contribution of all neutrons. As a matter of fact for a typical supernova at 10 kpc, about 1000 events are expected using a spherical detector of radius 4 m with Xe gas at a pressure of 10 Atm. A world wide network of several such simple, stable and low cost supernova detectors with a running time of a few centuries is quite feasible.