Beyond Born-Oppenheimer approximation in ultracold atomic collisions (original) (raw)

We report on deviations beyond the Born-Oppenheimer approximation in the potassium interatomic potentials. Identifying three up-to-now unknown d-wave Feshbach resonances, we significantly improve the understanding of the 39 K inter-atomic potentials. Combining these observations with the most recent data on known inter-and intra-isotope Feshbach resonances, we show that Born-Oppenheimer corrections can be determined from atomic collisional properties alone and that significant differences between the homo-and heteronuclear case appear.