Direct observation of fine structure changing collisions in cold trapped Rb-85

We present an overview of two experimental methods that we have employed to study the fine structure changing collisional loss process in a magneto-op tical trap. Both methods are based in the cw and pulsed photoionization of the atomic fragments generated in such collisions. The contribution of this loss mechanism to the total trap-loss rate was directly determined in both cases. The dependence of the fine structure changing loss rate with the li ght intensity and frequency were investigated using detection through pulse d ionization. The different approaches that had to be used for each of the two methods, as the results obtained from the two techniques, are discussed .