Using ion production to monitor the birth and death of a metastable helium Bose Einstein condensate

We discuss observations of the ion flux from a cloud of trapped 2 3 S 1 metastable helium atoms. Both Bose–Einstein condensates (BEC) and thermal clouds were investigated. The ion flux is compared with time-of-flight observations of the expanded cloud. We show data concerning BEC formation and decay, as well as measurements of two-and three-body ionization rate constants. We also discuss possible improvements and extensions of our results.