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arXiv · 2605.16243

Stern--Gerlach Spin Sorting and Dynamical Feedback in Relativistic Pair-Plasma Reconnection

K. Nykyri
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Abstract

We derive a Stern--Gerlach control parameter, $\Xi$, comparing spin-driven cross-sheet displacement with the relativistic Larmor radius. It places heliospheric plasmas and most astrophysical jets in the negligible regime, some stellar-mass black-hole coronae in a transitional regime, and magnetar sheets in a strong, near-QED regime. Relativistic pair-plasma simulations at fixed $\gamma_{\rm tr}=2$ show that increasing $\Xi$ produces, within the coupled SG+$\mathbf J_M$ model, magnetic-moment sorting and magnetization-current feedback that enhance the normalized flux-growth rate through an additional spin-kinetic pathway beyond classical pressure- and geometry-controlled pair-plasma reconnection.

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K. Nykyri. 2026-05-15. Stern--Gerlach Spin Sorting and Dynamical Feedback in Relativistic Pair-Plasma Reconnection. https://arxiv.org/abs/2605.16243

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