Collisional losses in a K-Rb cold mixture - art. no. 013413

We have observed a heteronuclear trap loss rate for a mixture of trapped K- 39 and Rb-85 atoms. Our results indicate that hyperfine changing collision and radiative escape dominate in the low and high intensity regimes, respec tively. They are also consistent with radiative escape taking place with th e participation of the doubly excited state potential (K*-Rb*). A Gallagher -Pritchard model taking into account the doubly excited channel was impleme nted, reproducing the experimental results well qualitatively. The values o btained for the cross species trap loss indicate possibilities of future ex periments with this mixture.