Plasma Rotation Induced by Biasing in Axially Symmetric Mirrors

TL;DR

This paper analyzes plasma rotation driven by biasing in linear traps, considering different plasma parameters and transport mechanisms, to understand how angular momentum is generated and dissipated in axially symmetric mirror devices.

Contribution

It introduces a comprehensive analysis of plasma rotation mechanisms in linear traps, accounting for line-tying effects and radial transport in different plasma regimes.

Findings

Line-tying effects influence plasma rotation in traps with good plasma parameters.

Radial transport dominates angular momentum loss in low-density, turbulent traps.

Scrape-off layer conditions partially determine maximum achievable rotation.

Abstract

Physics of the plasma rotation driven by biasing in linear traps is analyzed for two limiting cases. The first, relevant for traps with decent plasma parameters, considers the line-tying effects to be responsible for the drive as well as for the dissipation of the angular momentum. Meanwhile, in long and thin traps with low plasma parameters or developed turbulence the radial transport of the angular momentum becomes its primary loss channel. The momentum flux goes into the scrape-off layer; that makes conditions there partially responsible for the achievable rotation limits.