Motion of negative ions in superfluid³He

Abstract

The motion of negative ions in superfluid 3He when acted on by a field is calculated using a model in which the cross-section is taken to be constant. The theory is developed for both the A and B-phase It is argued that the scattering processes can be treated as being elastic for temperatures close to the transition temperature. The theory is in good agreement with experimental results for the B-phase of superfluid 3He for velocities in excess of the critical velocity. It is possible to estimate the energy gap from the data. The theory is not in agreement with experimental results for lower velocities. This implies that the momentum transfer cross-section is smaller than in the normal phase for quasiparticle scattering processes.