Supernova neutrino halo may determine heavy-element production

Discovery News : When a massive star collapses into a neutron star and produces a supernova, it also releases waves of neutrinos. Those neutrinos scatter off material falling inward toward the neutron star, creating a neutrino halo through which successive waves of outward-flowing neutrinos must pass. Although models predict that a negligibly small fraction of outward-flowing neutrinos are scattered in the halo, a new supercomputer simulation indicates otherwise. John Cherry of the University of California, San Diego, has found that neutrino–neutrino scattering could be strong enough to have an impact on both the flavor of the neutrinos that pass through the halo and the kinds of elements heavier than lithium that are produced by the supernova.