Supernova matter at subnuclear densities as a resonant Fermi gas:   Enhancement of neutrino rates
  At low energies nucleon-nucleon interactions are resonant and therefore supernova matter at subnuclear densities has many similarities to atomic gases with interactions dominated by a Feshbach resonance. We calculate the rates of neutrino processes involving nucleon-nucleon collisions and show that these are enhanced in mixtures of neutrons and protons at subnuclear densities due to the large scattering lengths. As a result, the rate for neutrino pair bremsstrahlung and absorption is significantly larger below 10^{13} g cm^{-3} compared to rates used in supernova simulations. 
A. Bartl, C.J. Pethick, A. Schwenk
nucl-th astro-ph.SR hep-ph