Hot nuclear fluorescence in the LiI crystal

Abstract

AbstractResonance scattering of γ‐radiation by Li nuclei is considered in a LiI crystal. In this crystal hot nuclear fluorescence is the main scattering process a t energies of ≈ 477 keV, whereas at a fixed scattering angle the spectral distribution of the scattered quanta depends essentially on the direction of the incident beam. Calculations are made for the orientational effects expected in the case of backward‐scattered quanta registered by a resonant detector. It is shown that the signal of such a detector as a function of mutual orientation of the crystal and the incident beam has sharp (of ≈6° width) maxima of a reasonable intensity in the [100] and [111] directions. The connection between the obtained angular characteristics, the details of the relaxation process in the crystal lattice, and the specific form of the interatomic potential are discussed.