Fig. 4: ICCD analysis and Ozone measurement in 1 g conditions.

a Filtered ICCD acquisitions of a plasma treatment of a grounded target at 15 mm. Contrast and the brightness adjustment are optimally set up for each acquisition. b ICCD acquisitions of a 7 kV, 20 kHz He plasma treatment of a grounded target versus different reactor-target gaps: 15 mm, 20 mm, 25 mm. Contrast and brightness adjustment are the same for each acquisition. c ICCD intensities of different transitions at the surface of a 15 mm far grounded target for a He (black) and a He + 0.5% O₂ (red) gas mixture for a plasma at 20 kHz and 7 kV. Presented values are means ± SD of n = 10 replicates. d Ozone measurement versus the O₂ concentration at 20 kHz and 7 kV. The target is at 15 mm, metallic, and grounded. Presented values are means of n = 10 replicates.