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 Na-2 bound states, a Na photoassociation experiment, a nd a recent observation of field-induced Feshbach resonances in a Na Bose c ondensate. We obtain a set of Na interaction parameters that is in excellen t agreement with all these experimental data. The existing discrepancy betw een different values for the scattering length a(1,-1) of Na atoms in the / 1,-1] hyperfine state is resolved. The present interaction parameters enabl e us to give accurate predictions for the singlet and triplet scattering le ngths 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 unobse rved Feshbach resonances. We find a(S)=(19.1+/-2.1)a(0), a(T)=(65.3+/-0.9)a (0), and a(1,-1)(B=0)=(55.4+/-1.2)a(0). [S1050-2947(99)04401-7].