Ideal gases in time-dependent traps - art. no. 061601

We investigate, theoretically, the properties of an ideal trapped gas in a time-dependent harmonic potential. Using a scaling formalism, we are able t o present exact analytical results for two important classes of experiments : free expansion of the gas upon release of the trap and the response of th e gas to a harmonic modulation of the trapping potential. We present specif ic results relevant to current experiments on trapped fermions.