The differences and similarities between the internal transport barriers (ITBs) of tokamak and
helical plasmas are reviewed. By comparing the characteristics of the ITBs in tokamak and …

Plasmas are created by heating gases through the absorption of ionizing radiation in the
visible through the ultraviolet part of the electromagnetic spectrum and through collisional …

Turbulence is widely expected to limit the confinement and, thus, the overall performance of
modern neoclassically optimized stellarators. We employ novel petaflop-scale gyrokinetic …

Recently, experiments on basic plasma physics issues for solving future problems in fusion
energy have been performed on a Large Helical Device. There are several problems to be …

In this study, we discovered a turbulence transition in a large helical device. The turbulence
level and turbulence-driven energy transport decrease to a specific transition density and …

Global gyrokinetic simulations of electrostatic microturbulent transport for discharge#
166256 of the Large Helical Device stellarator in the presence of boron impurity show the co …

A novel reduced model for ion temperature gradient (ITG) turbulent transport in helical
plasmas is presented. The model enables one to predict nonlinear gyrokinetic simulation …

A new bursting m= 1/n= 1 instability (m, n: poloidal and toroidal mode numbers) with rapid
frequency chir** down has been observed for the first time in a helical plasma with intense …

Global gyrokinetic simulations of ion temperature gradient (ITG) and trapped electron mode
(TEM) in the LHD stellarator are carried out using the gyrokinetic toroidal code (GTC) with …

We assess the magnetic field configuration in modern fusion devices by comparing
experiments with the same heating power, between a stellarator and a heliotron. The key …