Coherent structures in ηi-mode turbulence

Abstract
Numerical simulations of the ion‐temperature‐gradient‐driven mode (ηi‐ mode) show that long‐lived, large‐scale coherent structures exist and play an important role in the study of the anomalous transport. In this work, the stationary solutions of the nonlinear equations describing the dynamics of the ηi ‐mode are investigated. The simplest solution is found to be a dipolar vortex in the shearless case. In the presence of the magnetic shear, a modified dipolar vortex solution is found through perturbation theory.