On the possibility of detecting the annihilation of very heavy neutrinos in the galactic halo by 1 km^3 volume neutrino detectors

We consider the possibility of detecting in a hypothetical 1 km^3 neutrino telescope high energy neutrinos resulting from the annihilation of very heavy neutrinos of fourth generation in the galactic halo. It is shown that such a large telescope could in principle detect this negligible component which, if it does exist, gives a contribution of order 10^-2 to the dark matter of the universe