title: Tokamak equilibria with toroidal-current reversal in the plasma core consistent with experimental data.
abstract: For the first time, tokamak equilibria with negative toroidal current flowing in the plasma core are computed consistently with available measurements from typical current-hole discharges. The equilibrium reconstruction, which leads to non-nested configurations where a system of axisymmetric magnetic islands unfolds, yields an overall good agreement between the computed and experimental plasma-pressure profiles, together with an excellent fit to motional-Stark-effect data. Therefore, considering the accuracy limits of present-day experimental results, care must be exercised when ruling out the existence of tokamak equilibria with central toroidal-current reversal, particularly if relying on reconstruction tools that cannot cope with non-nested configurations.
authors.affiliation: Centro de Fusão Nuclear, Associação Euratom-IST, Instituto Superior Técnico, 1049-001 Lisboa, Portugal. par@cfn.ist.utl.pt
authors.forename: Paulo
authors.initials: P
authors.lastname: Rodrigues
authors.forename: João P S
authors.initials: JP
authors.lastname: Bizarro