Electron drift velocity in gases at high E/N

Abstract
The relationship between the theoretical (v) and experimental (vexp) values of the electron drift velocity is investigated for electron swarms at high E/N. In the presence of ionization the experimental methods do not directly measure the electron drift velocity (v) as specified in the transport equation and calculated by solving Boltzmann's equation. The correlation factor relating the two velocities has been evaluated for four different experimental techniques. For E/N-282 Td the ratio v/vexp is as large as 1.53 for helium and 1.24 for hydrogen.