Measured absolute density profiles of He-I 1s2s 3S1 metastables between the electrodes - (a) for N = 1 and 0.05 % of O2, (b) and (c) for N = 4 and two different concentrations of the O2 admixture of 0.05 % and 0.2 % at fixed z = −15 mm. The base frequency is f0 = 13.56 MHz and the peak-to-peak value of the driving voltage waveform is kept constant at 500 V.
Experimental data are marked as exp
Calculated data are marked as calc
x [mm] , y [cm^-3]
(Figure9a-9b): Exp absolute density profiles of He-I 1s2s 3S1 metastables for O2-admixtures of 0.05% and N=1 and N=4 respectively
(Figure9c): Exp absolute density profiles of He-I 1s2s 3S1 metastables for O2-admixtures of 0.2% for N=4