Phase-space entropy cascade and irreversibility of stochastic heating in nearly collisionless plasma turbulence
(2023)
Prevention of core particle depletion in stellarators by turbulence
Physical Review Research American Physical Society 5:2 (2023) L022053
Abstract:
In reactor-relevant plasmas, neoclassical transport drives an outward particle flux in the core of large stellarators and predicts strongly hollow density profiles. However, this theoretical prediction is contradicted by experiments. In particular, in Wendelstein 7-X, the first large optimized stellarator, flat or weakly peaked density profiles are generally measured, indicating that neoclassical theory is not sufficient and that an inward contribution to the particle flux is missing in the core. In this Research Letter, it is shown that the turbulent contribution to the particle flux can explain the difference between experimental measurements and neoclassical predictions. The results of this Research Letter also prove that theoretical and numerical tools are approaching the level of maturity needed for the prediction of equilibrium density profiles in stellarator plasmas, which is a fundamental requirement for the design of operation scenarios of present devices and future reactors.Isotope effects on intrinsic rotation in hydrogen, deuterium and tritium plasmas
Nuclear Fusion IOP Publishing 63:4 (2023) 044002
3D magnetic field measurements and improvements at the negative ion source BATMAN Upgrade
Fusion Engineering and Design Elsevier 189 (2023) 113471
New linear stability parameter to describe low-β electromagnetic microinstabilities driven by passing electrons in axisymmetric toroidal geometry
Plasma Physics and Controlled Fusion IOP Publishing 65:4 (2023) 045011