This paper studies a continuous atmospheric-pressure discharge maintained by focused subterahertz radiation of a 263-GHz gyrotron. A plasma torch propagating toward microwave radiation was sustained on an argon flow exiting a metal gas tube in the surrounding atmosphere of air. Using a high-speed camera, the spatial structure of the torch was studied, and the temporal dynamics on timescales of the order of 20 ns was examined. The emission spectra of the optical wavelength range were used to estimate the excitation temperature of argon atoms and electron density. It was shown that a discharge of this type is substantially non-equilibrium, and the electron temperature is many times higher than the vibrational and gas temperatures, being 1.5–1.7 eV in order of magnitude. The electron density measured by the Stark broadening of the Нα and Нβ hydrogen lines exceeds a critical value for the frequency of the heating field and is at a level of 1.5 10¹⁵ cm⁻³.

中文翻译：

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太赫兹辐射准光学光束中维持的非平衡大气压等离子体炬

本文研究了由263 GHz回旋管的聚焦太赫兹辐射维持的连续大气压放电。向着微波辐射传播的等离子炬在离开金属气体管的氩气流中保持在周围的大气中。使用高速相机，研究了火炬的空间结构，并研究了时间尺度为20 ns的时间动态。使用光波长范围的发射光谱估算氩原子的激发温度和电子密度。结果表明，这种放电基本上是不平衡的，电子温度是振动和气体温度的几倍，为1.5–1.7 eV。¹⁵ 厘米^-3。