Neutrino interactions may explain supernova explosions

A recent theoretical calculation of neutrino–nucleon cross sections, based on neutral currents, has revived interest in a model that proposes neutrino interactions as the mechanism for explosions in supernovae. The neutrino idea was first suggested by Stirling Colgate of the New Mexico Institute of Mining and Technology and Richard White of the Lawrence Livermore Laboratory. Subsequent calculations were performed by W. David Arnett of the University of Texas and by L. N. Ivanova, V. S. Inshennik and D. K. Nadezhin at the Institute of Applied Mathematics of the USSR Academy of Sciences. A more refined calculation by James R. Wilson (Lawrence Livermore Laboratory) showed that the neutrino interaction then assumed (from the theory by Richard Feynman and Murray Gell‐Mann) was of the wrong form to account for explosions. Now Daniel Z. Freedman of the National Accelerator Laboratory has found that if neutral currents exist, the scattering of neutrinos by nuclei is coherent; thus the cross sections go as the square of the atomic weight. Wilson has redone his earlier calculations with the new cross sections and has found that they can account for explosions, depending on what values are assumed for the neutral‐current coupling constant and for the muon–neutrino opacity.