The study of cold collisions involving different species

In this work we present an overview in a sequence of experiments in heteron uclear cold collisions. As a first step in the process to understanding the se processes we have studied trap losses due to crossed species interaction . Using a magneto-optical trap, which can trap any pair of the following at oms Na, K, Rb and Cs, we have measured trap loss rate (beta') for Na-K, Na- Rb, K-Rb, and Rb-Cs mixtures. Through the variation of beta' with one speci es trap laser intensity one can understand the mechanisms which lead to los ses. This is an important first step for any further experiment involving t wo different species.