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arXiv 2201.05157physics.plasm-phastro-ph.SR
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非平衡空间等离子体中传输系数的实际估算

Towards a realistic evaluation of transport coefficients in non-equilibrium space plasmas

Edin Husidic, Klaus Scherer, Marian Lazar, Horst Fichtner, Stefaan Poedts

摘要:

最近的研究概述了对空间等离子体中输运系数的评估的兴趣,其中观察到的等离子体粒子的速度分布不仅受到二元碰撞的影响,例如,在低能量下,但也通过粒子与波湍流和波动的相互作用而激发,产生超热卡帕分布的种群。本文提供了基于正则化Kappa分布(RKDs)的主要输运系数的第一次估计,与标准Kappa分布(SKDs)不同,它使宏观参数化没有数学分歧或物理不一致。这里导出的所有输运系数,即对于所有的$κ> 0$值,扩散系数和迁移率系数、电导率、热电系数和热导率是有限的并且是明确定义的。此外,对于低的$κ$值(即,低于SKD极点),输运系数可能比相应的麦克斯韦极限高几个数量级,这意味着如果忽略超热电子,则可能会大大低估。

英文摘要:

Recent studies have outlined the interest for the evaluation of transport coefficients in space plasmas, where the observed velocity distributions of plasma particles are conditioned not only by the binary collisions, e.g., at low energies, but also by the energisation of particles from their interaction with wave turbulence and fluctuations, generating the suprathermal Kappa-distributed populations. This paper provides a first estimate of the main transport coefficients based on regularised Kappa distributions (RKDs), which, unlike standard Kappa distributions (SKDs), enable macroscopic parameterisation without mathematical divergences or physical inconsistencies. All transport coefficients derived here, i.e., the diffusion and mobility coefficients, electric conductivity, thermoelectric coefficient and thermal conductivity, are finite and well defined for all values of $κ> 0$. Moreover, for low values of $κ$ (i.e., below the SKD poles), the transport coefficients can be orders of magnitudes higher than the corresponding Maxwellian limits, meaning that significant underestimations can be made if suprathermal electrons are ignored.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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