Fizeau effect for neutrons passing through matter at a nuclear resonance

Abstract

We have measured the phase shift of a neutron de Broglie wave induced by the motion of Sm-149 through which the neutron is propagating. This experiment differs from a number of ‘neutron Fizeau’ experiments carried out in recent years. The observed phase shift is caused by the motion of the matter itself, and not by the motion of its boundaries, as was the case with the earlier experiments. In this regard our experiment is a true neutron analog of the famous Fizeau experiment of 1859, where phase shift of the light wave interference pattern was induced by the motion of matter.