JT-60U MONTHLY SUMMARY

Oct - Dec 2002

19th IAEA Fusion Energy Conference, Lyon, 14-19 October 2002.

As a summary of the JT-60 project in 2001-2002, twenty-one papers (11 orals and 10 posters) were presented as follows:

  1. Overview of JT-60U Results toward High Integrated Performance in Reactor-Relevant Regime [OV/1-3], T. Fujita and the JT-60 Team.
  2. Achievement of a High Fusion Triple Product and Steady State Sustainment in High βp ELMy H-mode Discharges in JT-60U [EX/C2-2], A. Isayama, et al.
  3. Stable Existence of Central Current Hole in the JT-60U Tokamak [EX/C3-1Ra], Y. Miura, et al.
  4. Studies of Current Profile Optimization and Influence of Electron Heating towards Advanced Tokamak Operation on JT-60U [EX/C3-3], S. Ide, et al.
  5. Relationship between Particle and Heat Transport in JT-60U Plasmas with Internal Transport Barrier [EX/C3-5Rb], H. Takenaga, et al.
  6. Fast Dynamics of Type I ELM and Transport of ELM Pulse in JT-60U [EX/S1-1], N. Oyama, et al.
  7. Heating and Current Drive by Electron Cyclotron Waves in JT-60U [EX/W-2], T. Suzuki, et al.
  8. Property of Alfven Eigenmode in JT-60U Reverse Shear and Weak Shear Discharges [EX/W-6], M. Takechi, et al.
  9. Driving Mechanism of SOL Plasma Flow and Effects on the Divertor Performance in JT-60U [EX/D1-3], N. Asakura, et al.
  10. Enhanced Pedestal Pressure and Parameter-linkages Determining Edge Pedestal Structures in JT-60U Type I and Type II ELMy H-mode [EX/P2-04], Y. Kamada, et al.
  11. Property of Internal Transport Barrier Formation in JT-60U [EX/P2-08], Y. Sakamoto, et al.
  12. Objectives and Design of the JT-60 Superconducting Tokamak [FT/2-5], S. Ishida, et al.
  13. Advanced Fusion Technologies Developed for JT-60 Superconducting Tokamak [FT/P2-09], A. Sakasai, et al.
  14. Improvement of Beam Performance in Negative-Ion Based NBI System for JT-60U [CT/6Rd], N. Umeda, et al.
  15. Development of Gyrotron and JT-60U EC Heating System for Fusion Reactor [CT/7Ra], K. Sakamoto, et al.
  16. Study of Integrated High-Performance Regimes with Impurity Injection in JT-60U Discharges [EX/P2-03], K.W. Hill, et al.
  17. Role of Low Order Rational q Values in the ITB-events in JT-60U Plasmas [EX/P2-06], S.V. Neudatchin, et al.
  18. Tritium Distribution on Plasma Facing Graphite Tiles of JT-60U [EX/P2-11], T. Tanabe, et al.
  19. Fast Particle Destabilization of TAE Type Modes in NSTX, JT-60U and Planned Burning Plasma Devices [TH/7-1Rb], C.Z. Cheng, et al.
  20. High Mach Flow Associated with Plasma Detachment in JT-60U [TH/P2-15], A. Hatayama, et al.
  21. Formation of an Advanced Tokamak Plasma without the Use of Ohmic Heating Solenoid in JT-60U [PD/T-2], Y. Takase, et al.

Tritium Degassing

Since tritium inventory in the vacuum vessels has to be controlled for safety in fusion reactors, establishment of effective tritium degassing methods is a critical issue. Degassing of tritium produced by DD reaction has intensively been studied in JT-60U from October to December.

Using glow, ECR and Taylor discharge cleaning, tritium degassing was investigated. Hydrogen, deuterium, helium and argon were used for the working gases. Dependence of tritium concentration in the exhausted gas on the vacuum vessel temperature was surveyed by changing the temperature from the room temperature to 300C. The glow discharge cleaning using hydrogen was found to be the most efficient for the tritium degassing in the studied cleaning procedures.