A possible Mössbauer effect in neutron capture

Direct radiative neutron capture onto a nucleus embedded in a lattice leads to recoil effects that are somewhat more complicated in principle than those present for conventional Mössbauer absorption, emission or resonant scattering processes. We have explored the theory for such recoil effects, and have found: (1) that under conditions in which the momentum of the incident neutron and emitted gamma are matched approximately, a Mössbauer pip that is broadened and shifted is predicted to occur; (2) that in the presence of highly nonthermal lattice excitation, possible anomalously large energy transfer with the lattice is predicted.