Absolute measurement of the excitation rate and density of the excited species in an RF discharge from optical emission spectroscopy

A simple method of ray tracing is adopted to calibrate the absolute value of the net production rate by electron impact of excited species with short radiative lifetime in a discharge. As an example, the net excitation rate and density of Ar(3p 5 ) are measured in the RF glow discharge at 13.56 MHz, 1 Torr in Ar.