Microwave resonator method is a well established and sensitive technique of plasma density measurements, especially in low pressure plasmas. The traditional Slater approximation of very small electromagnetic field perturbation is extended and corrected by a more accurate, yet relatively simple numerical model, also addressing further phenomena such as the resonator eigenmodes and the stability of the dominant mode. The presence of a discharge tube is found to be a main source of deviation from the Slater approximation. The pre-calculated numerical correction factors are directly applicable for a range of cavity and discharge tube geometries.

中文翻译：

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用于等离子体诊断的微波共振腔法的数值增强

微波谐振器方法是一种成熟且敏感的等离子体密度测量技术，尤其是在低压等离子体中。通过更精确但相对简单的数值模型扩展和校正了非常小的电磁场扰动的传统Slater逼近，还解决了其他现象，例如谐振器本征模和主导模的稳定性。发现放电管的存在是与Slater近似偏差的主要来源。预先计算的数值校正因子可直接应用于各种腔体和放电管的几何形状。