On the dispersion law of neutrons in accelerated matter

In recent experiments with ultracold neutrons, a change in the energy occurring when neutrons pass through an accelerated reflecting sample was detected. The results are in good agreement with theoretical predictions obtained under the assumption that the dispersion law of neutron waves in accelerated matter is the same as that in a sample at rest. Some reasons that this assumption is valid only when the acceleration is below a certain critical value have been presented. A possible experimental test of these reasons has been discussed.