Plasma heating and confinement using the

1
Plasma heating and confinement using
the long-pulse, modulated DNB
R. Granetz, D. Beals, S.Scott, PSFC

• Proof-of-principle done with 50 ms DNB
• ?W?1 kJ, barely discernible at 0.6 MA
• Too noisy to get ? from break-in-slope
• Take advantage of the new long-pulse (1.5 s),
  modulated DNB to allow signal averaging in order
  to extract small ?W, and cleaner temporal signal,
  from background noise
• Need long, steady flattops modulated beam
• Parameter scans during single discharge

Alcator C-Mod Ideas Forum, 10-12 Sept 2003
2
Results from proof-of-principle experiments with
short-pulse DNB
3
Preliminary comparison of discharges with and
without locked modes