Comparison of Langmuir Probe and Spectrometric Electron Temperature Measurements

Langmuir probes, because of their convenience and their ability to give time-resolved measurements, are often used for temperature measurements in plasmas. Since probe results are subject to suspicion, we compare probe and spectrometric electron temperature measurements in a particular low-temperature plasma in which this is possible. We find probe temperatures to be significantly higher over an electron temperature range (measured spectrometrically) of at least 410° to 820°K.