  The inelastic magnetic scattering of neutrons from thin superconducting films
irradiated with microwave radiations, is analyzed. This process is due to the
interaction of the magnetic field generated by the neutron, with the
oscillating current induced by the electromagnetic field penetrated into the
film. In the Born approximation, the neutron energy can both increase and
decrease by the energy quantum of the field. The scattering cross section,
which increases with decreasing the field frequency, is derived, and its
numerical calculations are carried out. Measurements of this cross section give
directly the frequency-dependent supercurrents in the films.
