Species composition in the CO2discharge laser

The composition of a sealed discharge in He-N
2
-CO
2
and He-CO
2
mixtures was studied with a quadrupole mass spectrometer. A modulated molecular beam sampling technique allowed direct measurement of the molecular, atomic, and ionic species produced in the discharge. Effective formation and destruction rates were measured for various species. In particular, the nitrogen oxides, NO and NO
2
, are formed in sufficient quantities to affect the performance of CO
2
lasers. In the He-N
2
-CO
2
mixture the dominant ion changes from CO-
2
to NO+, while in He-CO
2
, O+
2
becomes the major ion.