Interference of γ Radiation in the Spin Space during Nuclear Resonance Scattering

In the multispace interference pattern appearing during nuclear resonance scattering of γ radiation in an iron borate crystal, along with the interference in the geometrical and energy spaces, interference in the spin space [1] plays a significant role. The latter appears due to specific nature of hyperfine interaction of the Fe-57 nucleus with crystalline fields in iron borate [2]. To single out this peculiar form of interference and to study its properties and the effect on the general pattern of scattering, the scattering of γ radiation from a single nucleus is investigated upon the excitation of an isolated resonant transition between the ground and excited states of the nucleus. The amplitudes and polarizations of radiation waves are determined for each of partial paths of scattering in the spin space. The strong dependence of the interference conditions on the polarization of incident radiation and on the direction of the crystal magnetic field at the nucleus is revealed. Apart from polarization properties of scattered radiation, the nuclear resonance scattering spectra are investigated.