-
2012
This paper presents the DYON simulations of the plasma burn-through phase at Joint European Torus (JET) with the ITER-like wall. The main purpose of the study is to validate the simulations with the International Thermonuclear Experimental Reactor (ITER)-like wall, made of beryllium. Without impurities, the burn-through process of a pure deuterium …
-
2012
A real-time system has been developed to trigger both the MAST Thomson scattering (TS) system and the plasma control system on the phase and amplitude of neoclassical tearing modes (NTMs), extending the capabilities of the original system. This triggering system determines the phase and amplitude of a given NTM using magnetic coils at different tor…
-
2012
The neutron field parameters (fluence and energy distribution) at a specific location outside the JET Torus Hall have been measured by means of super-heated fluid detectors (or “bubble detectors”) in combination with an independent, time-of-flight, technique. The bubble detector assemblies were placed at the end of a vertical line of sight at a…
-
2012
A new beam emission spectroscopy turbulence imaging system has recently been installed onto the MAST spherical tokamak. The system utilises a high-throughput, direct coupled imaging optics, and a single large interference filter for collection of the Doppler shifted emission from the ~2 MW heating beam of ~70 keV injection energy. The collected lig…
-
2012
The physics of kinetic effects on the resistive wall mode (RWM) stability is studied, and a comparison between reversed field pinch (RFP) and Tokamak configurations is made. The toroidal, magnetohydrodynamic (MHD)-kinetic hybrid stability code MARS-K, in which the drift kinetic effects are self-consistently incorporated into the MHD formulation, is…
-
2012
The transport of injected beam ions due to toroidal magnetic field ripple in the mega-ampere spherical tokamak (MAST) is quantified using a full orbit particle tracking code, with collisional slowing-down and pitch-angle scattering by electrons and bulk ions taken into account. It is shown that the level of ripple losses is generally rather low, al…
-
2012
Within the single fluid theory for a toroidal, resistive plasma, the favorable average curvature effect [Glasser et al. , Phys. Fluids 18 , 875 (1975)], which is responsible for the strong stabilization of the classical tearing mode at finite pressure, can also introduce a strong screening effect to the externally applied resonant magnetic field. C…
-
2012
Significant progress has been made in interpreting the effects of non-axisymmetric “error” fields on a plasma through ideal MHD stability and a dominant “least stable” ideal mode through which the fields couple to the tearing resonant surface. However, in contrast to expectations from such theories, experiments have found limited success in…
-
2011
An energetic-particle (EP)-driven “off-axis-fishbone-like mode (OFM)” often triggers a resistive wall mode (RWM) in JT-60U and DIII-D devices, preventing long-duration high-b N discharges. In these experiments, the EPs are energetic ions (70–85 keV) injected by neutral beams to produce high-pressure plasmas. EP-driven bursting events reduce t…
-
2011
A detailed experiment-theory comparison reveals that linear ideal MHD theory is in quantitative agreement with external magnetic and internal soft x-ray measurements of the plasma response to externally applied non-axisymmetric fields over a broad range of beta and rotation. This result represents a significant step toward the goal of advancing the…
Showing 301 - 310 of 507 UKAEA Paper Results