Conference Papers

Showing 1 - 5 of 5 Conference Paper Results
2020
UKAEA-CCFE-CP(20)71
27th IAEA Fusion Energy Conference, Ahmedabad, India, 22-27 October 2018

The fast-ion transport has been investigated in low-collisionality discharges at ASDEX Upgrade and TCV using offaxis neutral beams. In both devices Alfven eigenmode activity was observed which does, however, not strongly affect the global fast-ion confinement. In contrast, charge exchange losses have been identified to have a strong effect. At TCV …

Preprint
2019
UKAEA-CCFE-CP(20)69
16th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems, Shizuoka City, Japan, 3-6 September 2019

Elliptical AE (EAE) and TAE mode instabilities have been observed in hydrogen-rich (nH/(nH+nD)~70-90% JET discharges of so-called “three-ion scenario”, i.e. D-(3He)-H three ion ICRH scenario [1], which is characterized by strong absorption of radio frequency waves a…

Preprint Published
2019
UKAEA-CCFE-CP(19)43
46th European Physical Society Conference on Plasma Physics (EPS), Milan, 8-12 July 2019

The resonant detection and measurement of the damping rates of Alfvén Eigenmodes (AEs) is of critical importance to the design of experiments and development of models of AE stability [1]. With the Alfvén Eigenmodes Active Diagnostic (AEAD) on JET, weakly-damped Toroidal AEs (TAEs) have been probed. Theoretical modeling using the Gyrokinetic Toro…

Preprint Published
2018
UKAEA-CCFE-CP(18)11
27th IAEA Fusion Energy Conference, Ahmedabad, India, 22-27 October 2018

Results of simulations of the sawtooth-induced redistribution of fast ions in JET and ITER with the code OFSEF are presented. The dependence of the redistribution on the particle parameters (energy and pitch angle) is studied. The redistribution of the trapped and marginally passing particles is found to exhibit barrier-like behaviour at the separa…

Preprint Published
2018
UKAEA-CCFE-CP(18)04
27th IAEA Fusion Energy Conference, Ahmedabad, India, 22-27 October 2018

An edge resonant transport layer has been found to explain many aspects of fast-ion confinement under symmetry breaking 3D edge perturbations, such as edge localized modes (ELMs) and externally applied magnetic perturbations (MPs). Experimental measurements in the ASDEX Upgrade (AUG) tokamak show that fast-ion losses in the presence of symmetry bre…

Preprint Published