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arXiv · 2610.32085

Plasma transport by carrier electrons: delocalization length for heat-flux

C. A. Walsh
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Abstract

The delocalization length $λ_d=λ_{ei} Z/\sqrt{Z+4.45}$ is an improved heat-flux non-locality metric accounting for the localizing effect of electron-electron collisions on the electron population carrying heat-flux. Magnetization also localizes the carrier electrons; the delocalization Hall parameter $ψ_d=13.5 χZ/(Z+4.62)$ shows that this occurs at a faster rate than magnetization of thermal conductivity ($ψ_κ= 9.94χ(Z+0.17)/(Z+5.88)$). The traditional Knudsen number, which uses the electron-ion mean-free path, does not fairly represent non-locality across ionization and magnetization; $Kn_d = 8.28λ_{d\bot}/L_T$ should instead be used. The kinetic understanding of the three magnetized heat-flux components is unified in the linear regime with a full electron-electron collision operator and a converged harmonic expansion of the electron distribution (up to $f_6$). Righi-Leduc heat-flux is found to delocalize easier than its perpendicular counterpart, due to its carriers being higher energy electrons. This approach lays the groundwork for a consistent treatment of the kinetically-modified induction equation.

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C. A. Walsh. 2026-10-23. Plasma transport by carrier electrons: delocalization length for heat-flux. https://arxiv.org/abs/2610.32085

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