title: Access to a new plasma edge state with high density and pressures using the quiescent H mode.
abstract: A path to a new high performance regime has been discovered in tokamaks that could improve the attractiveness of a fusion reactor. Experiments on DIII-D using a quiescent H-mode edge have navigated a valley of improved edge peeling-ballooning stability that opens up with strong plasma shaping at high density, leading to a doubling of the edge pressure over the standard H mode with edge localized modes at these parameters. The thermal energy confinement time increases as a result of both the increased pedestal height and improvements in the core transport and reduced low-k turbulence. Calculations of the pedestal height and width as a function of density using constraints imposed by peeling-ballooning and kinetic-ballooning theory are in quantitative agreement with the measurements.
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA.
authors.forename: W M
authors.initials: WM
authors.lastname: Solomon
authors.affiliation: General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA.
authors.forename: P B
authors.initials: PB
authors.lastname: Snyder
authors.affiliation: General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA.
authors.forename: K H
authors.initials: KH
authors.lastname: Burrell
authors.affiliation: Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Fenstermacher
authors.affiliation: General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Garofalo
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Grierson
authors.affiliation: ITER Organization, Route de Vinon sur Verdon, CS 90 046, 13067 Saint Paul Lez Durance Cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Loarte
authors.affiliation: University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.forename: G R
authors.initials: GR
authors.lastname: McKee
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA.
authors.forename: R
authors.initials: R
authors.lastname: Nazikian
authors.affiliation: General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA.
authors.forename: T H
authors.initials: TH
authors.lastname: Osborne