Diffraction Image of a Point Source of Slow Neutrons in a Weakly Deformed Crystal

The problem of dynamic diffraction of slow neutrons from a point source on the spatial lattice of a crystal with a weak deformation field is considered. The study is based on the asymptotic representation of the Green-Riemann function for a pair of Hamilton’s equations of the hyperbolic type and describes the propagation of quasi-amplitudes of slow neutrons diffracted waves in a crystal lattice. The conditions for focusing one of the wave modes inside the crystal are considered. The main parameters of the focal spots inside of the lattice were investigated depending on the distance between the source of slow neutrons and the crystal. The behavior of focal spots from the parameter of the deformation field was also analyzed in detail.