J. M. Park,
Neutral beam current drive NBCD experiments in DIII-D using vertically shifted plasmas to move the current drive away from the axis have clearly demonstrated robust off-axis NBCD. Time-dependent measurements of magnetic field pitch angles by the motional Stark effect diagnostic are used to obtain the evolution of the poloidal magnetic flux, which i…
PublishedA. Thyagaraja K. G. McClements
Equations describing the nonrelativistic motion of a charged particle in an arbitrary noninertial reference frame are derived from the relativistically invariant form of the particle action. It is shown that the equations of motion can be written in the same form in inertial and noninertial frames, with the effective electric and magnetic fields in…
PublishedS. Khakshouri D. M. Duffy
Tungsten is a strong contender for a plasma-facing material in future fusion power plant designs, and the material of choice for the divertor of ITER, due to its high melting point, thermal conductivity, and resistance to sputtering erosion. Sputtering erosion is a major concern for plasma-facing materials because sputtered atoms could enter the pl…
PublishedV.F.Shevchenko M.R.O’Brien D.Taylor Mast Team
Electron Bernstein wave (EBW) assisted plasma current start-up has been demonstrated for the first time in a tokamak. It was shown that plasma currents up to 17 kA can be generated non- inductively by 100 kW of RF power injected. With optimized vertical field ramps, plasma currents up to 33 kA have been achieved without the use of solenoid flux. It…
PublishedE.S. Marmar A. Bader M. Bakhtiari H. Barnard W. Beck I. Bespamyatnov A. Binus P. Bonoli B. Bose M. Bitter I. Cziegler G. Dekow et al.
This paper summarizes highlights of research results from the Alcator C-Mod tokamak covering the period 2006 through 2008. Active flow drive, using mode converted waves in the ion cyclotron range of frequencies (ICRF), has been observed for the first time in a tokamak plasma, using a mix of D and 3 He ion species; toroidal and poloidal flows are dr…
PublishedColin Windsor Geoff Cottrell Richard Kemp
Recent predictions have been made of metallurgical properties of low-activation ferritic/martensitic steels alloys at the high irradiation levels (displacements per atom or dpa) needed for a fusion power plant as based on measurements at low irradiation levels where more data is available. These have been published for the yield stress and for the …
PublishedK. Tanaka K. Kawahata T. Tokuzawa T. Akiyama M. Yokoyama M. Shoji C. A. Michael L. N. Vyacheslavov S. Murakami A. Wakasa A. Mishchenko K. Muraoka S. Okajima H. Takenaga Lhd Experiment Group
Particle confinement processes are studied in detail on the Large Helical Device (LHD). Diffusion coefficients (D) and convection velocities (V) are estimated from density modulation experiments. The magnetic configuration and collisionality are widely scanned in order to investigate parameter dependences of D and V. To study the effect of the magn…
PublishedE. Lerche V. Bobkov P. Jacquet M.L. Mayoral A. Messiaen et al.
Using the JET A2 ICRF antennas [1], experiments were carried out to assess the performance of three different dipole phasing configurations relevant for the operation of the ICRF antenna in ITER. Three similar discharges with dipole, "symmetric dipole" and "super dipole" phasings were compared. In the "super dipole" case, higher coupling was confir…
PublishedV. Shevchenko A. Saveliev
Electron Bernstein waves (EBW) have the potential to provide highly localized heating and current drive (CD). EBWs are predominantly electrostatic and they damp on electrons near electron cyclotron harmonics without momentum injection into the plasma. These features represent a powerful tool for understanding transport and stability phenomena by lo…
Published