Shielding from instantaneously and adiabatically applied potential wells in collisionless plasmas

The response of collisionless plasmas to an applied potential can differ from classic Debye shielding, and when the potential is rapidly applied ~‘‘instantaneous shielding’’!, the shielding can differ from when it is slowly applied ~‘‘adiabatic shielding’’!. Experiments demonstrate that when a test potential well is applied to a one-dimensional pure-electron plasma, instantaneous and adiabatic shielding are similar for small potentials, but that instantaneous shielding is weaker than adiabatic shielding for large potentials. These results have been confirmed with particle-in-cell computer simulations. Simulations also show that the peculiar distribution functions of instantaneously and adiabatically shielded plasmas agree with theoretical predictions. © 2002 American Institute of Physics. @DOI: 10.1063/1.1455633#