First-principles closure for cross-field electron mobility in Hall thrusters · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title
First-principles closure for cross-field electron mobility in Hall thrusters
Plain
Thruster simulation codes currently need a hand-tuned correction factor for how easily electrons cross the magnetic field. A formula derived from physics would make the codes predictive.
Precise · changed · core
Revision 1: In Hall thrusters (radial $B$ of order 100 to 300 G, xenon propellant), the measured cross-field electron mobility exceeds the classical collisional value by one to three orders of magnitude and varies along the channel. Derive a closure mu_perp(z) from local plasma parameters that, inserted in fluid or hybrid codes, predicts thrust, discharge current and breathing-mode oscillations to within 10 percent without tuning, across thrusters and operating points.
Revision 2: In Hall thrusters (radial $B$ of order 100 to 300 G, xenon propellant), the measured cross-field electron mobility exceeds the classical collisional value by one to three orders of magnitude and varies along the channel. Derive a closure $\mu_{\mathrm{perp}}(z)$ from local plasma parameters that, inserted in fluid or hybrid codes, predicts thrust, discharge current and breathing-mode oscillations to within 10 percent without tuning, across thrusters and operating points.
Settled by
A closure that predicts measured performance of at least two different thrusters across operating points without adjustment.
Kind
phenomenon
Answer type
mechanism
References
(empty)
Literature status
open
Status note
3D particle-in-cell simulations in 2025-2026 resolve the electron drift instability and near-wall transport paths (e.g. arXiv:2603.14849), but no tuning-free closure exists.
Posed since
(empty)

Decisions