Hyperfine-changing collision measurements in trap loss for mixed species in a magneto-optical trap

Trap-loss rates due to hyperfine-structure-changing collisions involving co ld Na and K atoms in a mixed species magneto-optical trap have been measure d. The investigations were performed in the low intensity regime, where hyp erfine-structure-changing collision are believed to be the dominant mechani sm for atomic losses. Comparison between homonuclear (Na-Na) and heteronucl ear (Na-K) collision rate coefficients reveals a higher loss rate in the ca se of heteronuclear collisions. Results obtained in the regime of low trap laser intensity are compared with existent loss rates for several alkali me tals, showing themselves to be in good agreement with those expected. [S105 0-2947(99)02211-8].