Electron energy distributions in the mercury discharge positive column

The electron energy distribution functions in mercury discharge positive columns are measured by the Druyvestyn second differential method and compared to those calculated numerically from the Boltzmann equation under the same discharge conditions. The discharge parameters are measured directly and fed into the Boltzmann equation computation code. The shapes of the distributions are found to agree approximately but the mean energies have large disagreement. A method of obtaining the measured distribution from the calculation by modifying the data fed into the computation code and correlating the result with the simple electron temperature measurement is suggested.