Gamma photons from parametric resonance in neutron stars
  Shock waves in cold nuclear matter, e.g. those induced by a collision of two neutron stars, can generate a large number of gamma photons via parametric resonance. We study the resonant production of gamma rays inside a shocked neutron star and discuss the possible astrophysical consequences of this phenomenon. 
Juan Garcia-Bellido (Imperial College) and Alexander Kusenko (UCLA)