  We investigate the interaction of a laser-cooled trapped ion (Ba$^+$ or
Rb$^+$) with an optically confined $^{87}$Rb Bose-Einstein condensate (BEC).
The system features interesting dynamics of the ion and the atom cloud as
determined by their collisions and their motion in their respective traps.
Elastic as well as inelastic processes are observed and their respective cross
sections are determined. We demonstrate that a single ion can be used to probe
the density profile of an ultracold atom cloud.
