Prospects for Neutrino-Antineutrino Transformation in Astrophysical   Environments
  We examine whether the newly derived neutrino spin coherence could lead to large-scale coherent neutrino-antineutrino conversion. In a linear analysis we find that such transformation is largely suppressed, but demonstrate that nonlinear feedback can enhance it. We point out that conditions which favor this feedback may exist in core collapse supernovae and in binary neutron star mergers. 
Alexey Vlasenko, George M. Fuller, Vincenzo Cirigliano
astro-ph.HE hep-ph