Two-stage processes in the mercury positive column

A number density balance is set up for the processes involving ions, the 6 3 P levels and resonance radiation in mercury over the pressure range 1 mtorr to 1 torr. In this way the transition from single-stage to two-stage processes dominating as the electron density increases is explored. The variation of electron temperature is derived and comparison made with the experiments of Mierdel and Schmalenberg in 1936.