New experiment on non-stationary neutron diffraction by a traveling surface acoustic wave

Abstract

The results of a new experiment on neutron diffraction by surface acoustic waves are presented. The measurements were carried out at a fixed incident angle in the time-of-flight mode, which made it possible to study the diffraction pattern in a wide range of neutron wavelengths at surface acoustic wave frequencies from 35 to 117 MHz. In a number of cases, diffracted waves of not only the first but also the second order were observed. The measurement results of both the angular distribution of diffracted waves and their amplitudes are in satisfactory agreement with the calculations. A new estimation has been obtained for the range of applicability of the dispersion law of neutron waves in matter moving with large acceleration.