We developed an extension of the spectrometric method to estimate a reduced electric field (E/N), which is applicable in nitrogen-containing plasmas. The method is based on the intensity ratio of the emission bands of the first negative system (FNS) of and the second positive system (SPS) of N2. It uses the emission occurring in the wavelength interval 375–410 nm, which includes six SPS and two FNS bands. The choice of the spectral window is guided by much simpler acquisition and processing of experimental data than the SPS(0, 0) and FNS(0, 0) pair that is typically used. Following this idea, we construct a kinetic model for pure molecular nitrogen, which determines the population of the upper states responsible for the FNS and SPS emission. Moreover, we perform sensitivity analysis of the kinetic model, which allows us to reveal the most significant processes for the investigated intensity ratios. For these processes, we provide an in-depth review of the kinetic data that are available in the literature. We use the fact that the spectral window investigated contains bands to obtain three independent intensity ratios with sufficient signal-to-noise ratio ((FNS(0, 0)/SPS(0, 2), FNS(0, 0)/SPS(1, 4), FNS(0, 0)/SPS(2, 5)), which are usable for more accurate electric field determination. We also provide analytical formulas representing intensity ratio dependencies on E/N. Furthermore, we focus on different spectrometric representations of FNS and SPS bands, which also affect the precision of E/N determination. We examine the FNS/SPS band profiles in terms of different rotational temperatures and instrumental functions. Finally, we propose a simple procedure that enables the use of bandhead intensities in the intensity ratio dependencies, thus avoiding the need to evaluate integral band intensities from the recorded spectra.

中文翻译：

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从 N ₂ ⁺和 N ₂波段强度比确定电场：纯氮中的非平衡瞬态放电

我们开发了光谱测量方法的扩展，以估计减小的电场 (E/N)，这适用于含氮等离子体。该方法基于 N2 的第一个负系统 (FNS) 和第二个正系统 (SPS) 的发射带的强度比。它使用发生在 375-410 nm 波长区间内的发射，其中包括六个 SPS 和两个 FNS 波段。光谱窗口的选择由比通常使用的 SPS(0, 0) 和 FNS(0, 0) 对简单得多的实验数据采集和处理指导。按照这个想法，我们构建了一个纯分子氮的动力学模型，它确定了负责 FNS 和 SPS 发射的上层状态的数量。此外，我们对动力学模型进行敏感性分析，这使我们能够揭示所研究的强度比的最重要过程。对于这些过程，我们对文献中可用的动力学数据进行了深入审查。我们利用研究的光谱窗口包含带的事实来获得具有足够信噪比的三个独立强度比（(FNS(0, 0)/SPS(0, 2), FNS(0, 0)/SPS( 1, 4), FNS(0, 0)/SPS(2, 5)), 可用于更精确的电场测定。我们还提供了表示强度比对 E/N 依赖性的解析公式。此外，我们关注不同的FNS 和 SPS 波段的光谱表示，这也影响 E/N 测定的精度。我们根据不同的旋转温度和仪器功能检查 FNS/SPS 波段轮廓。最后，