Dynamics and generation mechanisms of mesoscale structures in tokamak edge plasmas

Intermittent convective-like plasma transport associated with mesoscale coherent structures extended along the magnetic field lines (“blobs”) is often dominant at the edge of tokamaks, stellarators, and linear devices. Blobs can travel a large distance toward the wall (∼10 cm and larger) and strongly enhance both edge plasma energy and particle transport and plasma-wall interactions. The dynamics of blobs and blob generation mechanisms are discussed in this paper.