The effect of the orientations of electric and magnetic fields on the electron mean energy and drift velocity in a partially ionized gas

Abstract

The present investigation attempts to analyze the influence of the orientations of the imposed magnetic and electric fields on the mean electron energy and drift velocity. For this purpose, the electron velocity distribution function relating to the presence of the external fields with arbitrary orientations is first studied. The analysis is based on the Lorentz approximation and it is assumed that the electron velocity distribution is deter­mined essentially by the electron-atom collisions. The mean electron energy is discussed for two different cases: (1) contant mean free path and (2) constant collision time. In the case of constant collision time, the drift velocity as well as the electron current density is calculated. The Hall conductivity is expressed in a general form which depends upon the direction of the magnetic field with respect to the electrical field. Besides this, an additional com­ponent of the current is theoretically observed; in general, it vanishes if the magnetic field is either parallel or perpendicular to the electric field.