Experimental exploration of profile control in the Princeton Beta Experiment-Modified (PBX-M) tokamak

Journal Article · Thu Jul 01 04:00:00 EDT 1993 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860744· OSTI ID:6423061

Bernabei, S; Bell, R; Chance, M; Chu, T K; Corneliussen, M; Davis, W; Gettlefinger, G; Gibney, T; Greenough, N; Hatcher, R; Hermann, H; Ignat, D; Jardin, S; Kaita, R; Kaye, S; Kessel, C; Kozub, T; Kugel, H; Lagin, L; LeBlanc, B ; Manickam, J; Okabayashi, M; Oliver, H; Ono, M; Paul, S; Preische, S; Roney, P; Sauthoff, N; Schweitzer, S; Sesnic, S; Sun, Y; Takahashi, H; Tighe, W; Valeo, E; von Goeler, S; Voss, K ^[1]; Mauel, M; Navratil, G ^[2]; Cesario, R ^[3]; Batha, S; Levinton, F ^[4]; Rimini, F ^[5]

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1. Princeton University, Plasma Physics Laboratory, Forrestal Campus, P. O. Box 451, Princeton, New Jersey 08543 (United States)
2. Department of Applied Physics, Columbia University, 206 SW Mudd Building, New York, New York, 10027 (United States)
3. EURATOM-ENEA sulla Fusione, CRE Frascati, C.P. 65, 00044-Frascati, Rome (Italy)
4. Fusion Physics and Technology, 3547 Voyager Street, Suite 104, Torrance, California 90503-1673 (United States)
5. JET Joint Undertaking, Abingdon

The experimental program of the Princeton Beta Experiment-Modified (PBX-M) tokamak [Phys. Fluids B[bold 2], 1271 (1990)] is directed toward tailoring plasma profiles to achieve greater stability and confinement and to gain access to the second stability region. Modification of the current density profile has been achieved with lower-hybrid current drive (LHCD), leading to a regime free of global magnetohydrodynamic modes, while raising the value of [ital q](0) above unity. The diffusion of the fast electrons produced by LHCD has been examined using two-dimensional hard x-ray imaging. Ion Bernstein waves (IBW) have been used for ion heating: a preliminary analysis shows that ion heating was spatially localized and in agreement with theoretical calculations. Divertor biasing has modified the electric field inside the last closed surface, resulting in the formation of a transport barrier, which in turn has reduced the threshold power of neutral beam injection (NBI) for H-mode transition by 25%.

• DOE Contract Number: AC02-76CH03073
• OSTI ID: 6423061
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 5:7; ISSN 0899-8221; ISSN PFBPEI
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700350* -- Plasma Production
Heating
Current Drive
& Interactions-- (1992-)
BERNSTEIN MODE
CLOSED PLASMA DEVICES
CONFINEMENT
CURRENT DENSITY
DIVERTORS
ELECTROMAGNETIC RADIATION
ELECTRON DENSITY
HEATING
HIGH-FREQUENCY HEATING
IONIZING RADIATIONS
LOWER HYBRID HEATING
OSCILLATION MODES
PLASMA CONFINEMENT
PLASMA HEATING
RADIATIONS
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
X RADIATION