On plasma density blobs in drift turbulence

TL;DR

This paper demonstrates that large plasma density blobs can form within drift wave turbulence, with densities up to three times the average, aligning with experimental observations.

Contribution

It introduces a model incorporating the nonlinear Boltzmann factor, showing the formation of plasma density blobs within drift wave dynamics.

Findings

Plasma density blobs can reach about three times the average density.

Blob formation is consistent with experimental observations.

The model aligns theoretical predictions with experimental data.

Abstract

By keeping nonlinear Boltzmann factor in electron density dependence on electrostatic potential it is demonstrated that large plasma density blobs, often seen in experiment inside separatrix, can exist within the framework of drift wave dynamics. The estimates show that plasma density in a blob can be ~3 times higher that average plasma density, but hardly exceeds this limit, which in a ball park is in agreement with experimental observations.