Response of the electric field in a positive column in helium to a current perturbation

摘要

The response of the electric field in a positive column of a hot cathode discharge in helium to a current perturbation has been measured over a wide pressure range. The relaxation of the electric field, electron density, and drift velocity proceed via a two timehyphen;constant process which can be interpreted as being due to direct electron impact ionization of helium atoms in the ground state and the production and subsequent ionization of metastable helium atoms in the 23Sstate.