N and C-atoms in R (Ar)-N2-CH4 Flowing Afterglows at High Pressure

The production of N-atom density has been analysed in Ar-N2 high pressure flowing afterglows after HF plasmas at a frequency from 13.6 Mhz to 2450 MHz. The plasma length increased when the HF frequency decreased from 2450 to 13.6 MHz and by lowering x in the Ar-xN2 gas mixture.

It was found that the N+N recombination on the N2(B,v’) states was reduced by 2.5 for v’=11, by 10 for v’=8 and by 30 for v’=0 by going from pure N2 to Ar-2%N2.

The production of N and C-atoms in Ar-N2-xCH4 with x=10-3 – 10-2 showed a drop of N and C-atoms at x=10-2 which should result of N+CH3 reactions. The CH3 and C-atom density was about 4 1011 cm-3 in a Ar-17%N2-1%CH4 gas mixture at 14 Torr.