Neutron laue diffraction in a weakly deformed crystal at the Bragg angles close to π/2

An essential magnification of an external force acting on a diffracting neutron for the Bragg angles θ_B close to the right one is observed. Any external action (caused by either crystal deformation or external force affected the neutron) results in a bend of the so called “Kato trajectories” inside the crystal and, for the case of a finite crystal, gives considerable variation of the intensities of both diffracted neutron beams (direct and reflected). It is shown that the magnification factor is proportional to tan² (θ_b) and can reach (10²−10³) for Bragg angles surfficiently close to 90°. The text was submitted by the authors in English.