Theoretical aspects of incoherent nuclear resonant scattering

The influence of nonrotational atomic motion on the scattering of X-rays by nuclei with sharp resonances is investigated. Two incoherent scattering ch annels, nuclear resonant fluorescence and nuclear resonant absorption follo wed by conversion electron emission and atomic fluorescence, are studied in detail. Time dependence and cross sections for these processes are given. In both cases, the cross section is proportional to the self-intermediate s cattering function of the resonant isotope. The influence of other X-ray sc attering processes on incoherent nuclear resonant scattering is discussed. We find that incoherent scattering channels dominate in off-resonance excit ations. Self-intermediate scattering functions for the ideal gas and the ha rmonic lattice are calculated.