Loss rate of an electrically trapped non-neutral plasma

A non-neutral plasma in a Malmberg–Penning trap can be allowed to escape confinement in a controllable way, because the depth of the applied electric potential well used to confine the plasma axially is adjustable. A theoretical approach is presented for predicting the collision-based axial plasma loss rate, just after the well depth in the trap is made shallower. The approach can also be used for predicting an upper limit for the loss rate of a near-thermal plasma from other types of traps, which may employ one-, two-, or three-dimensional electric potential wells. Example predictions are provided, and comparisons with existing theories are made.