In this work, we present a method for absolute measurement of air fluorescence yield based on high resolution optical emission spectroscopy. The absolute measurement of the air fluorescence yield is feasible using the Cherenkov light, emitted by an electron beam simultaneously with the fluorescence light, as a “standard candle”. The separation of these two radiations can be accomplished exploiting the “dark” spectral regions of the emission band systems of the molecular spectrum of nitrogen. In these “dark” regions the net Cherenkov light can be recorded experimentally and be compared with the calculated one. The instrumentation for obtaining the nitrogen molecular spectra in high resolution and the noninvasive method for monitoring the rotational temperature of the emission process are also described. For the experimental evaluation of the molecular spectra analysis we used DC normal glow discharges in air performed in an appropriate spectral lamp considered as an air-fluorescence light emulator. The proposed method and the associated instrumentation could be tested and used in thin or thick target experiments in electron beam accelerators as a candidate optical system for this purpose.

在这项工作中，我们提出了一种基于高分辨率光学发射光谱的绝对测量空气荧光产率的方法。使用电子束与荧光同时发射的切伦科夫光作为“标准蜡烛”，可以绝对测量空气荧光的产生量。可以利用氮分子光谱的发射带系统的“暗”光谱区域来实现这两种辐射的分离。在这些“黑暗”区域，可以通过实验记录净的切伦科夫光，并将其与计算出的光进行比较。还描述了用于以高分辨率获得氮分子光谱的仪器以及用于监视发射过程的旋转温度的非侵入性方法。为了进行分子光谱分析的实验评估，我们使用了在适当的光谱灯中进行的空气中的直流正辉光放电，该光谱灯被视为空气荧光灯模拟器。可以测试所提出的方法和相关的仪器，并将其用于电子束加速器的薄或厚目标实验中，以此作为候选光学系统。