We postulate that basic radiative signatures observed during the initial phases of nanosecond discharge in liquid water can be attributed to the electron–neutral bremsstrahlung process. Principal characteristics of the radiation collected from developing luminous filaments consist of a sharp decrease in the emission intensity at the short-wavelength side of the spectra, followed by a maximum and subsequent decrease in intensity towards near-infrared wavelengths. All these radiative features can be attributed to the electron–neutral bremsstrahlung produced by a bell-like energy distribution of the electrons. Such an electron energy distribution function is coherent with the concept of electric field emission into electrostriction-induced nanovoids. The findings of this work help in elucidating the hitherto unclear mechanism(s) of plasma generation in liquid water.

我们假设在液态水中纳秒放电的初始阶段观察到的基本辐射特征可归因于电子-中性韧致辐射过程。从发展中的发光灯丝收集的辐射的主要特征包括在光谱的短波长侧的发射强度急剧下降，然后是最大和随后强度向近红外波长的下降。所有这些辐射特征都可以归因于电子的钟形能量分布产生的电子-中性韧致辐射。这种电子能量分布函数与将电场发射到电致伸缩诱导的纳米空隙中的概念相一致。