Stability of drift waves in a field reversed configuration

TL;DR

This paper investigates the stability of drift waves in field-reversed configurations, revealing how short connection lengths and ion Landau damping influence plasma transport stability.

Contribution

It derives a radial eigenmode equation from kinetic theory and analyzes the stability of universal modes considering the effects of connection length and temperature ratio.

Findings

Short connection lengths stabilize drift waves via ion Landau damping.

Stability depends on the ion to electron temperature ratio (Ti/Te).

The model uses the cylindrical Bennett pinch approximation for analysis.

Abstract

The drift waves in field-reversed configurations without a toroidal magnetic field, therefore no shear, play an important role in plasma transport. The short connection length of the poloidal field in these systems leads to significant stabilization by influencing the wave particle resonance. The field reversed configuration is modeled by the cylindrical Bennett pinch in the limit of large aspect ratio. The radial eigenmode equation for the universal mode is derived from kinetic theory and the method of quadratic forms is used to study its stability. The short connection lengths of the field lines lead to ion Landau damping on the inside of the plasma and the stability of the mode depend on the value of the temperature ratio Ti/Te