Open AccessHigh-Harmonic Fast Wave Driven H-mode Plasmas on NSTX
Author(s) -
B P LeBlanc,
R E Bell,
S I Bernabei,
K Indireshkumar,
S M Kaye,
R Maingi,
T K Mau,
D W Swain,
G Taylor,
P M Ryan,
J B Wilgen,
J R Wilson
Publication year - 2003
Language(s) - English
Resource type - Reports
DOI - 10.2172/812904
Subject(s) - plasma , atomic physics , electron , electron temperature , kinetic energy , harmonic , ohmic contact , pedestal , joule heating , physics , nuclear physics , archaeology , electrode , quantum mechanics , history
The launch of High-Harmonic Fast Waves (HHFW) routinely provides auxiliary power to NSTX plasmas, where it is used to heat electrons and pursue drive current. H-mode transitions have been observed in deuterium discharges, where only HHFW and ohmic heating, and no neutral beam injection (NBI), were applied to the plasma. The usual H-mode signatures are observed. A drop of the Da light marks the start of a stored energy increase, which can double the energy content. These H-mode plasmas also have the expected kinetic profile signatures with steep edge density and electron temperature pedestal. Similar to its NBI driven counterpart--also observed on NSTX-- the HHFW H mode have density profiles that features ''ears'' in the peripheral region. These plasmas are likely candidates for long pulse operation because of the combination of bootstrap current, associated with H-mode kinetic profiles, and active current drive, which can be generated with HHFW power