Role of the interaction between neutron magnetic moments in neutron-neutron scattering

In the variable-phase approach, the interaction between magnetic moments is shown to have a considerable effect on spin-triplet neutron-neutron scattering for center-of-mass energies below 300 keV. It is found that, owing to the interaction of magnetic moments, all scattering phase shifts and mixing parameters at energies below 2 keV are proportional to the scattering momentum, that the differential cross section is isotropic, and that the total cross section does not approach zero in the low-energy limit and has a local minimum at about 20 keV. Simple formulas that take into account the interaction between neutron magnetic moments are obtained. These formulas make it possible to interpolate correctly phase shifts, mixing parameters, and cross sections for spin-triplet neutron-neutron scattering to the experimentally inaccessible energy range