A. Kirk I.T. Chapman T.E. Evans C. Ham J.R. Harrison G. Huijsmans Y. Liang Y.Q. Liu A. Loarte W. Suttrop A.J. Thornton
All current estimations of the energy released by type I ELMs indicate that, in order to ensure an adequate lifetime of the divertor targets on ITER, a mechanism is required to decrease the amount of energy released by an ELM, or to eliminate ELMs altogether. One such amelioration mechanism relies on perturbing the magnetic field in the edge plasma…
PublishedF. Militello P. Tamain W. Fundamenski A. Kirk V. Naulin A.H. Nielsen The Mast Team
Numerical simulations of interchange turbulence in the Scrape-Off Layer are performed in a regime relevant for a specific L-mode MAST (Mega Ampere Spherical Tokamak) discharge. Such a discharge was diagnosed with a reciprocating arm equipped with a Gundestrup probe. A detailed comparison of the average and statistical properties of the simulated an…
PublishedM. Turnyanskiy C. D. Challis R. J. Akers M. Cecconello D. L. Keeling A. Kirk R. Lake S. D. Pinches S. Sangaroon I. Wodniak
Previous experiments on MAST and other tokamaks have indicated that the level of fast ion redistribution can exceed that expected from classical diffusion and that this level increases with beam power. In this paper we present a quantification of this effect in MAST plasmas using a recently commissioned scanning neutron camera. The observed fast io…
PublishedA.Kirk I.T. Chapman Yueqiang Liu P. Cahyna P. Denner G. Fishpool C.J. Ham J.R. Harrison Yunfeng Liang E. Nardon S. Saarelma R. Scannell A.J. Thornton The Mast Team
Sustained ELM mitigation has been achieved using RMPs with a toroidal mode number of n=4 and n=6 in lower single null and with n=3 in connected double null plasmas on MAST. The ELM frequency increases by up to a factor of eight with a similar reduction in ELM energy loss. A threshold current for ELM mitigation is observed above which the ELM freque…
PublishedJ. R. Harrison G. M. Fishpool A. Kirk
The distribution of particles and power to plasma-facing components is of key importance in the design of next-generation fusion devices. Power and particle decay lengths have been measured in a number of MAST L-mode and H-mode discharges in order to determine their parametric dependencies, by fitting power and particle flux profiles measured by di…
PublishedG. Fishpool J. Canik G. Cunningham J. Harrison I. Katramados A. Kirk M. Kovari H. Meyer R. Scannell The Mast-Upgrade Team
A potentially important feature in a divertor design for a high-power tokamak is an extended and expanded divertor leg. The upgrade to MAST will allow a wide range of such divertor leg geometries to be produced, and hence will allow the roles of greatly increased connection length and flux expansion to be experimentally tested. This will include te…
PublishedS. Elmore S. Y. Allan A. Kirk A. J. Thornton J. R. Harrison P. Tamain M. Kocan J. W. Bradley The Mast Team
Knowledge of the ion temperature (Ti) is of key importance for determining heat fluxes to the divertor and plasma facing components, however data regarding this is limited compared to electron temperature (Te) data. Ti measurements at the divertor target, between edge-localised modes (inter-ELM) H-mode, have been made using a novel retarding field …
PublishedS. Y. Allan S. Elmore A. Kirk M. Kocan P. Tamain
Ion energy measurements have been made in the scrape off layer of the Mega Amp Spherical Tokamak (MAST) using a midplane retarding field energy analyser (RFEA) in H-mode plasmas during the inter-edge localised mode (ELM) period and during type I and type III ELMs. During the inter-ELM period at distances of 3 to 8 cm from the last closed flux surfa…
PublishedA.J. Thornton A. Kirk I.T. Chapman J.R. Harrison The Mast Team
Edge localised modes (ELMs) are a concern for future devices as they can limit the operational lifetime of the divertor. The mitigation of ELMs can be performed by the application of resonant magnetic perturbations (RMPs) which act to degrade the pressure gradient in the edge of the plasma. Investigations of the effect of RMPs on MAST have been per…
Published