A model realization of self-organized criticality for plasma confinement

TLDR

The paper presents a model for plasma transport near marginal stability. The model employs subcritical resistive pressure‑gradient‑driven turbulence and perturbative transport techniques to study pulse propagation. Nonlinear simulations reveal effective transport, self‑organized criticality features, and offer an explanation for nonlocal effects seen in tokamak experiments.

Abstract

A model for plasma transport near marginal stability is presented. The model is based on subcri- tical resistive pressure-gradient-driven turbulence. Three-dimensional nonlinear calculations based on this model show effective transport for subcritical mean profiles. This model exhibits some of the characteristic properties of self-organized criticality. Perturbative transport techniques are used to elucidate the transport properties. Propagation of positive and negative pulses is studied. The observed results suggest a possible explanation of the apparent nonlocal effects ob- served with perturbative experiments in tokamaks.