Skip to main content
eScholarship
Open Access Publications from the University of California

Enhanced localized energetic-ion losses resulting from single-pass interactions with alfvén eigenmodes

  • Author(s): Chen, X
  • Austin, ME
  • Fisher, RK
  • Heidbrink, WW
  • Kramer, GJ
  • Nazikian, R
  • Pace, DC
  • Petty, CC
  • Van Zeeland, MA
  • et al.
Abstract

We report the first observation of prompt neutral beam-ion losses due to nonresonant scattering induced by toroidal and reversed shear Alfvén eigenmodes in the DIII-D tokamak. The coherent losses are of full energy beam ions expelled from the plasma on their first poloidal orbit. The first-orbit loss mechanism causes enhanced, concentrated losses on the first wall exceeding nominal levels of prompt losses. The loss amplitude scales linearly with the mode amplitude. The data provide a novel and direct measure of the radial excursion or scatter of particles induced by individual modes and may shed light on the mechanism for the scattering of energetic particles in interstellar medium. © 2013 American Physical Society.

Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.

Main Content
Current View