Title :
A 70 keV neutral hydrogen beam injector with energy recovery for an MSE diagnostic application in fusion research
Author :
Simonin, A. ; Armitano, A. ; Brugnetti, R. ; Cano, V. ; Dougnac, H. ; Fazilleau, P.
Author_Institution :
DRFC, CEA Cadarache, Paul les Durance, France
Abstract :
A 70 keV 40 A hydrogen beam injector has been developed at Cadarache for a plasma diagnostic (MSE: Motional Stark Effect) to provide a measurement of the plasma current distribution in the Tore-Supra Tokamak. We present in this paper, the principle and the first experimental results of the injector, where a new type, and advantageous, energy recovery system, based on a magnetic neutraliser plasma confinement, has been developed. The hydrogen ion beam is accelerated to 70 keV with a three-grid multi-aperture system (aperture diameter Φ=11 mm) with an ion current density of ≈160 mA/cm2 . An ion source with a shape (height 1.2 m, width 80 mm) specifically adapted to the recovery system has been developed to meet the injector requirements: uniformity, high proton fraction (>80%) and high current density, ≈160 mA/cm2 over the whole extraction surface (900 cm2). A neutral beam power (H0 ) of 500 kW has been achieved with a divergence of ≈0.6° at 70 keV
Keywords :
Stark effect; Tokamak devices; collective accelerators; fusion reactor ignition; hydrogen neutral atoms; particle beam dynamics; particle beam extraction; particle beam fusion accelerators; particle beam stability; plasma beam injection heating; plasma collision processes; plasma density; plasma diagnostics; plasma heating; plasma toroidal confinement; plasma transport processes; 1.2 m; 40 A; 500 kW; 70 keV; 80 mm; H; MSE diagnostic application; Tore-Supra tokamak; beam divergence; beam uniformity; energy recovery; energy recovery system; fusion research; high current density; high proton fraction; hydrogen ion beam; ion current density; magnetic neutraliser plasma confinement; motional Stark effect; neutral hydrogen beam injector; plasma current distribution; plasma densities; plasma diagnostic; three-grid multiaperture system; whole extraction surface; Current density; Current measurement; Hydrogen; Particle beam injection; Particle beam measurements; Particle beams; Plasma confinement; Plasma diagnostics; Plasma measurements; Stark effect;
Conference_Titel :
Particle Accelerator Conference, 2001. PAC 2001. Proceedings of the 2001
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-7191-7
DOI :
10.1109/PAC.2001.987821
