Determination of collisional properties of cold Na atoms from analysis of bound-state photoassociation and Feshbach resonance field data

We review the information on the interactions between cold ground-state Na atoms following from Na₂ bound states, a Na photoassociation experiment, and a recent observation of field-induced Feshbach resonances in a Na Bose condensate. We obtain a set of Na interaction parameters that is in excellent agreement with all these experimental data. The existing discrepancy between different values for the scattering length a_1,-1 of Na atoms in the |1,-1〉 hyperfine state is resolved. The present interaction parameters enable us to give accurate predictions for the singlet and triplet scattering lengths a_S and a_T, a_1,-1, scattering lengths for collisions between Na atoms in other hyperfine states, and resonance fields of several yet unobserved Feshbach resonances. We find a_S=(19.1±2.1)a₀, a_T=(65.3±0.9)a₀, and a_1,-1(B=0)=(55.4±1.2)a₀.