S-wave and p-wave scattering in a cold gas of Na and Rb atoms

Abstract

Using improved experimentally based X1Σ+ and a3Σ+ molecular potentials of NaRb, we apply the variable phase method to compute new data for low energy scattering of 23Na atoms by 85Rb atoms and 87Rb atoms. These are the scattering lengths and volumes, numbers of bound states and effective ranges, which we use to obtain the low energy spin-change cross section as functions of the system temperature and the isotope masses. From an analysis of the contributions of s-wave and p-wave scatterings to the elastic cross section we estimate temperatures below which only s-wave scattering is dominant. We compare our quantal results to data obtained from the semiclassical approximation. We supply evidence for the existence of a near zero energy p-wave bound state supported by the singlet molecular potential.