z-logo
open-access-imgOpen Access
ELMs and the H-mode Pedestal in NSTX
Author(s) -
R. Maingi,
S. A. Sabbagh,
C. E. Bush,
E. D. Fredrickson,
J. Ménard,
D. Stutman,
K. Tritz,
M.G. Bell,
R. E. Bell,
J.A. Boedo,
D. Gates,
D. W. Johnson,
R. Kaita,
S. M. Kaye,
H. Kugel,
B.P. LeBlanc,
D. Mueller,
R. Raman,
A. L. Roquemore,
V. Soukhanovskii,
T. Stevenson
Publication year - 2004
Language(s) - English
Resource type - Reports
DOI - 10.2172/828497
Subject(s) - pedestal , plasma , scaling , atomic physics , magnetohydrodynamics , physics , mode (computer interface) , nuclear physics , geometry , mathematics , archaeology , history , computer science , operating system
We report on the behavior of ELMs in NBI-heated H-mode plasmas in NSTX. It is observed that the size of Type I ELMs, characterized by the change in plasma energy, decreases with increasing density, as observed at conventional aspect ratio. It is also observed that the Type I ELM size decreases as the plasma equilibrium is shifted from a symmetric double-null toward a lower single-null configuration. Type III ELMs have also been observed in NSTX, as well as a high-performance regime with small ELMs which we designate Type V. These Type V ELMs are consistent with high bootstrap current operation and density approaching Greenwald scaling. The Type V ELMs are characterized by an intermittent n=1 MHD mode rotating counter to the plasma current. Without active pumping, the density rises continuously through the Type V phase. However, efficient in-vessel pumping should allow density control, based on particle containment time estimates

The content you want is available to Zendy users.

Already have an account? Click here to sign in.
Having issues? You can contact us here