Collisional loss rate in a magneto-optical trap for sodium atoms: Light-intensity dependence

Abstract
We have measured the total collisional loss rate for ultracold sodium atoms held in a magneto-optical trap (MOT) as a function of light intensity in the trap. We extract the rate constant for collisional loss by measuring the temporal behavior of MOT loading from background vapor. The loss rate increases with light intensity in satisfactory agreement with new calculations, which are also presented. The results are interpreted in terms of detailed collision processes.