ELECTRON TEMPERATURE IN AC GLOW DISCHARGE AT AUDIO FREQUENCIES

The electron temperatures and electron densities in alternating discharges at audio frequencies excited between metal electrodes for various pressures have been measured by using the double probe method. The electron temperature is seen to remain constant for all frequencies up to 20 kc/s for any particular pressure. The electron temperature increases from 4·1 × 104 °K to 7·6 × 104 °K, while the electron density decreases from 6·3 × 108 electrons/cm3 to 4·4 × 108 electrons/cm3 as the pressure is reduced from 0·1 torr to 0·001 torr. The variation of electron temperature with pressure is seen to be similar to the corresponding variation in the case of the d.c. discharge showing that the a.c. discharges up to 20 kc/s are similar to d.c. discharges under similar conditions. © Taylor and Francis Group, LLC.