Reaching high poloidal beta at Greenwald density with internal transport barrier close to full noninductive current drive

J Hobirk; R C Wolf; O Gruber; A Gude; S Günter; B Kurzan; M Maraschek; P J McCarthy; H Meister; A G Peeters; G V Pereverzev; J Stober; W Treutterer; ASDEX Upgrade Team

doi:10.1103/PhysRevLett.87.085002

Reaching high poloidal beta at Greenwald density with internal transport barrier close to full noninductive current drive

Phys Rev Lett. 2001 Aug 20;87(8):085002. doi: 10.1103/PhysRevLett.87.085002. Epub 2001 Aug 2.

Authors

J Hobirk¹, R C Wolf, O Gruber, A Gude, S Günter, B Kurzan, M Maraschek, P J McCarthy, H Meister, A G Peeters, G V Pereverzev, J Stober, W Treutterer; ASDEX Upgrade Team

Affiliation

¹ Max-Planck-Institut für Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching, Germany.

PMID: 11497949
DOI: 10.1103/PhysRevLett.87.085002

Abstract

In the ASDEX Upgrade tokamak, high poloidal beta up to beta(pol) = 3 at the Greenwald density with H-mode confinement has been reached. Because of the high beta, the plasma current is driven almost fully noninductively, consisting of 51% bootstrap and 43% neutral beam driven current. To reach these conditions the discharge is operated at low plasma current ( I(P) = 400 kA) and high neutral beam heating power ( P(NBI) = 10 MW). The discharge combines an edge (H mode) and internal transport barrier at high densities without confinement-limiting MHD activities. The extrapolation to higher plasma currents may offer a promising way for an advanced scenario based fusion reactor.