Observation of Crossover from Ballistic to Diffusion Regime for Excimer Molecules in Superfluid ${}^4$He

D. E. Zmeev, F. Papkour, P. M. Walmsley +7

We have measured the temperature dependence of the time of flight of helium excimer molecules He2* in superfluid 4He and find that the molecules behave ballistically below 100mK an…