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

Abstract

We derive a Stern--Gerlach control parameter, $\hat{I}ž$, 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 ${\hat{I}}_{\mathrm{tr}}^3=2$ show that increasing $\hat{I}ž$ 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.

8 pages including six figures, supplementary material with 7 pages and 1 figure. This is a re-submission to PRL and companion paper, performing a relativistic sweep-study, SpinPIC2D code description, testing and validation has been submitted as companion paper to Physical Review E