Accessibility for lower hybrid waves in PBX-M

Technical Report · Thu Jul 01 04:00:00 EDT 1993

DOI:https://doi.org/10.2172/7368495· OSTI ID:7368495

Takahashi, H; Bell, R; Bernabei, S; Chance, M; Chu, T K; Gettelfinger, G; Greenough, N; Hatcher, R; Ignat, D; Jardin, S; Kaita, R; Kaye, S; Kugel, H; LeBlanc, B; Manickam, J; Okabayashi, M; Ono, M; Paul, S; Perkins, F; Sauthoff, N ; Sesnic, S; Sun, Y; Tighe, W; Valeo, E; von Goeler, S ^[1]; Batha, S; Levinton, F ^[2]

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1. Princeton Univ., NJ (United States). Plasma Physics Lab.
2. Fusion Physics and Technology

Understanding the wave damping mechanism in the presence of a spectral gap' is an important issue for the current profile control using Lower Hybrid Current Drive (LHCD). The authors examine a traditional explanation based upon upshifting of the wave parallel refractive index (n[sub [parallel]]) and find that there can be an upper bound in the n[sub [parallel]] upshift. The amount of upshift is not sufficient to bridge the spectral gap completely under some PBX-M LHCD conditions. There is experimental evidence, however, that current was driven even under such conditions. Another mechanism is also considered, based upon the 2-D velocity space dynamics coupled with a compound wave spectrum, here consisting of forward- and backward-running waves. The runaway critical speed relative to the phase speeds of these waves plays an important role in this model.

• Research Organization: Princeton Univ., NJ (United States). Plasma Physics Lab.
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 7368495
• Report Number(s): PPPL-2920; ON: DE93017513
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
700350 -- Plasma Production
Heating
Current Drive
& Interactions-- (1992-)
CLOSED PLASMA DEVICES
DAMPING
DATA
ELECTRON DRIFT
ELECTRONS
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FERMIONS
HEATING
HIGH-FREQUENCY HEATING
HYBRID RESONANCE
INFORMATION
LEPTONS
LIMITING VALUES
LOWER HYBRID CURRENT DRIVE
LOWER HYBRID HEATING
NON-INDUCTIVE CURRENT DRIVE
NUMERICAL DATA
OPERATION
OPTICAL PROPERTIES
PBX DEVICES
PHASE VELOCITY
PHYSICAL PROPERTIES
PLASMA HEATING
PLASMA WAVES
REFRACTIVE INDEX
RESONANCE
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
VELOCITY
WAVE FORMS