This article reports on experiments in a nonequilibrium plasma produced by nanosecond repetitively pulsed (NRP) spark discharges in water vapor at 450 K and atmospheric pressure. The objective is to determine the electron number density in the post-discharge, with spatial and temporal resolution, to gain a better understanding of the discharge development and chemical kinetics. Electron number densities were measured in water vapor from the broadenings and shifts of the H α and H β lines of the hydrogen Balmer series and of the atomic oxygen triplet at 777 nm. For an average reduced electric field of about 150 Td, high electron densities up to 3 × 10 18 cm −3 are measured at the cathode, up to 5 × 10 17 cm −3 at the anode, and up to 4 × 10 16 cm −3 in the interelectrode gap. The high density near the electrodes is attributed to ionization enhancement and secondary electron emission ...

中文翻译：

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大气压下水蒸气中纳秒级重复脉冲放电中电子数密度的测量

本文报道了在水蒸气在450 K和大气压下通过纳秒级重复脉冲（NRP）火花放电产生的非平衡等离子体中的实验。目的是通过空间和时间分辨率确定放电后的电子数密度，以更好地了解放电的发展和化学动力学。从氢巴尔默系列和原子氧三重态在777 nm处的Hα和Hβ线的加宽和位移测量了水蒸气中的电子数密度。对于平均约150 Td的减小的电场，在阴极处测量的电子密度高达3×10 18 cm -3，在阳极处测量的电子密度高达5×10 17 cm -3，并且高达4×10 16 cm电极间间隙为-3。