Passage of neutrons through accelerating crystal and the acceleration effect

TL;DR

This paper investigates how neutrons change energy when passing through an accelerating crystal near the Bragg condition, revealing a Doppler shift effect similar to refraction, supported by qualitative consistency with experimental data.

Contribution

It demonstrates that accelerating crystals induce neutron energy changes due to Doppler effects, extending understanding of neutron wave behavior under dynamic crystal conditions.

Findings

Neutron energy changes occur in accelerating crystals near Bragg condition.

The phenomenon is governed by Doppler frequency shifts at wave entry and exit.

Results align qualitatively with existing experimental observations.

Abstract

The problem of changing the energy of a neutron when it passes through an accelerating crystal under conditions close to the Bragg condition is considered. It is shown that, similar to the case of the passage of long-wavelength neutrons through a refractive sample, the accelerated motion of a crystal results in a change in neutron energy. The physical nature of the phenomenon in both cases is determined by the difference in the Doppler frequency shift at the entrance and exit of the wave through the sample. The difference between the case of ordinary refraction of long-wavelength neutrons and the case of wave passage through a crystal under conditions where diffraction has a dominant influence on the nature of wave propagation is only quantitative. The results obtained are qualitatively consistent with the available experimental data.