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

**Data Preview:**Note that by default the preview only displays up to 100 records. Use the pager to flip through more records or adjust the start and end fields to display the number of records you wish to see.

Resource Quantity: