Fast ion non-adiabaticity in spherical tokamaks

Breakdown of adiabatic invariance in spherical tokamaks

Thermal ions in spherical tokamaks have two adiabatic invariants: the magnetic moment and the longitudinal invariant. For hot ions, variations in magnetic-field strength over a gyro period can become sufficiently large to cause breakdown of the adiabatic invariance. The magnetic moment is more sensitive to perturbations than the longitudinal invariant and there exists an intermediate regime, su...

Psfc/ja-01-36 Electron Bernstein Waves in Spherical Tokamaks

In the electron cyclotron range of frequencies, the high-β NSTX plasmas are overdense to the traditional extraordinary X mode and/or the ordinary O mode. For low harmonics of the electron cyclotron frequency, the X and O modes are cutoff at the edge and for high harmonics the plasma is essentially optically thin to these modes. Thus, heating of such plasmas by electron cyclotron waves or diagno...

Current Drive by Electron Bernstein Waves in Spherical Tokamaks

This work was supported by the U.S. Department of Energy, Grant No. DE-FG02-91ER-54109, by the U.S. Department of Energy jointly with the National Spherical Torus Experiment, Grant No. DE-FG02-99ER-54521, and U.S. Department of Energy, Cooperative Grant No. DE-FC0299ER-54512. Reproduction, translation, publication, use and disposal, in whole or in part, by or for the United States government is...

Nuclear issues and analysis for ARIES spherical and advanced tokamaks

During the past few years, the ARIES team has developed advanced designs to identify the physics and technology areas of high leverage for achieving environmentally attractive and economically competitive fusion power plants. This paper documents the key neutronics parameters and identifies the nuclear issues for the most recent spherical and advanced tokamak designs. The nuclear assessment pla...

Bulk Ion Heating with ICRF Waves in Tokamaks