Microwave Measurements of the Radiation Temperature of Plasmas

Abstract
Radiation-temperature measurements of positive columns of glow discharges in helium, neon, and hydrogen were compared with calculations and with Langmuir probe measurements of the electron temperature. The microwave-noise radiation was detected at a frequency of 3000 Mc. The plasma studied was illuminated by a blackbody source of known variable temperature. The blackbody temperature was adjusted until the received noise power became independent of the presence of the unknown plasma. At this point, the temperature of the two radiators is the same, irrespective of the magnitude of the plasma absorptivity.