title: Energy-confinement scaling for high-beta plasmas in the W7-AS stellarator.
abstract: High-beta energy-confinement data are subjected to comparisons of scaling invariant, first-principles physical models. The models differ in the inclusion of basic equations indicating the nature of transport. The result for high-beta data of the W7-AS stellarator is that global transport is described best with a collisional high-beta model, which is different from previous outcomes for low-beta data. Model predictive calculations indicate the validation of energy-confinement prediction with respect to plasma beta and collisionality nu*. The finding of different transport behaviors in distinct beta regimes is important for the development of fusion energy based on magnetic confinement and for the assessment of different confinement concepts.
authors.affiliation: Max-Planck-Institut für Plasmaphysik, EURATOM-Association Wendelsteinstr. 1, Greifswald, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Preuss
authors.forename: A
authors.initials: A
authors.lastname: Dinklage
authors.forename: A
authors.initials: A
authors.lastname: Weller