AI 中文总结
本文通过低压火花实验观测到极向磁通量发射等特征，初步验证了受限等离子体动力学假说，提出需基于微扰理论重构等离子体模型，有望应用于天体物理及磁惯性约束聚变领域。
AI 中文摘要
本文以更优的实验和见解重新探讨了早期关于受限动力学假说的讨论[IEEE Trans. Plasma Sci. 41, 2013 pp. 437-446]。该假说涉及的观测结果为：载流等离子体的标准单流体运动方程包含受不同物理现象支配的项，这些现象被约束在差异极大的特征空间和时间尺度上演化，因此应能构造出方程无法在任何时刻都满足的反例。该假说假设，通常被忽略的电子惯性项会在这类反例中起作用，产生“异常”电子电流，其特征可在等离子体外被探测到，其中一个特征是与电流道螺旋形变无关的极向磁通量发射。基于上述论文的思路，开展了一系列低压火花实验，在火花道外部署了顺时针和逆时针抗磁回路、用于拦截方位角磁通量的静电屏蔽磁探针以及电位移探针。对多个预期特征的观测为该假说提供了初步验证，这表明等离子体连续统模型中对电子惯性的简单忽略，需改为基于与电子质量相关小参数的微扰理论重新开发这些模型，这可能为解决天体物理喷流轴向磁场起源等未解决问题提供重要见解，近固态密度的磁惯性约束聚变可能是潜在的实际应用。
英文摘要
This paper revisits an earlier discussion of the hypothesis of constrained dynamics [IEEE Trans. Plasma Sci. 41, 2013 pp. 437-446] with better experiments and insights. This hypothesis pertains to the observation that the standard single fluid equation of motion of a current-carrying plasma has terms governed by diverse physical phenomena which are constrained to evolve at widely mismatched characteristic space and time scales. It should then be possible to construct counterexamples where the equation cannot be satisfied at all times. The hypothesis posits that the usually neglected electron inertia terms come into play in such examples and create "anomalous" electron currents whose signatures can be detected outside the plasma. One of these signatures is emission of poloidal magnetic flux not attributable to a helical deformation of the current channel. Following the cue of the above-mentioned paper, a series of low-pressure spark experiments have been performed. Clockwise and counterclockwise diamagnetic loops, an electrostatically shielded magnetic probe oriented to intercept the azimuthal magnetic flux and an electric displacement probe are deployed outside the spark channel. Observation of several expected signatures provides a tentative validation of this hypothesis. This suggests that summary neglect of electron inertia in continuum models of plasma needs to be replaced by a redevelopment of these models based on perturbation theory with an electron-mass-related small parameter. Major insights could then arise into unsolved problems such as the origin of axial magnetic field in astrophysical jets. Near-solid-density magneto-inertial confinement fusion may be a potential practical application.
CommentsAccepted for publication in the Physics of Plasmas
