Fast Ion Confinement in High Beta, Steady-State Scenario Plasmas

POSTER

Abstract

Fast-ion confinement is studied for $q_{min}$ between 1.2-2.8 in plasmas with normalized $\beta > 2.6$. Fast-ion D-alpha (FIDA), neutron, and neutral-particle diagnostics measure the confined fast ions. Tearing modes and a ``sea'' of unstable Alfv\'en eigenmodes (AE) are observed. In preliminary analysis, the degradation in fast-ion confinement increases with $q_{min}$; increased AE activity appears responsible. Predictions of a model that assumes that AE-induced fast-ion transport is stiff are compared with the data.

*Work supported by the US Department of Energy under SC-G903402, DE-FC-02-04ER54698, DE-AC02-09CH11466, and DE-AC52-07NA27344.

Authors

  • W.W. Heidbrink

    • Irvine University, CA
    • UC Irvine
    • UC-Irvine
    • UCI
    • University of California Irvine

  • X. Chen

    • University of California Irvine

  • J.R. Ferron

    • General Atomics

  • M.A. Van Zeeland

    • General Atomics

  • B.A. Grierson

    • Princeton Plasma Physics Laboratory

  • C.T. Holcomb

    • Lawrence Livermore National Laboratory