Gas dynamics of pulsed low energy helium beams

We report data on pulsed atomic helium beams for use in an experiment on at omic reemission of atoms incident on a superfluid helium four sample. We us ed a gas dynamics code to model these pulsed low energy helium beams and fo und a good jit with the experimental results at low source pourer. The fit implies that significant collisional effects occur in these beams. Using th e modeller the incident pulsed beam which we obtained, we produced simulate d signals from the reemitted atoms which we expect to see in the experiment in which we monitor reemission from the sample when these atomic pulses ar e fired at it. We find that the present experiment could detect the propose d condensate mediated transmission process but that a larger superfluid sam ple would give a more definitive result.