K. Verhaegh B. Lipschultz J.R. Harrison N. Osborne A. Williams P Ryan J. Allcock J. Clark F. Federici B. Kool T. Wijkamp A. Fil D. Moulton O. Myatra A. Thornton T.O.S.J. Bosman C. Bowman B. Duval S. Henderson R. Scannell the MAST Upgrade team the EuroFusion MST1 team
In this paper we a first qualitative analysis of the atomic and molecular processes at play during detachment in the MAST-U Super-X divertor, using divertor spectroscopy data. Our analysis indicates a wide operational regime of detachment of the MAST-U super-X divertor, which can be roughly separated in four phases: 1) The ionisation front detac…
PreprintH. Anand D. Eldon H. Q. Wang G. McArdle L. Pangione M. Kochan
A local flux expansion method has been proposed for estimating the strike point position for the advanced divertor configuration on MAST Upgrade tokamak. The paper discusses the application and assesses the performance of the technique on a long-legged divertor plasma configuration on an operating device – the DIII-D tokamak. A comparison of …
Preprint PurchaseJ. R. Harrison T. Farley G. M. Fishpool A. Kirk B. Lipschultz J. Lovell F. Militello D. Moulton P. Ryan R. Scannell A. J. Thornton K. Verhaegh L. Xiang
The benefits of an optimised Super-X divertor configuration in mitigating the steady-state power and particle fluxes to the surfaces of the MAST Upgrade divertor have been quantified by performing a detailed comparison with a conventional divertor for the first time. In otherwise identical plasmas with conventional and Super-X divertor configu…
PreprintJ. W. Berkery S. A. Sabbagh L. Kogan D. Ryan J. M. Bialek Y. Jiang D. J. Battaglia S. Gibson C. Ham
Reconstructions of plasma equilibria using magnetic sensors and a Dα constraint were routine during operation of the MAST spherical tokamak, but reconstructions using kinetic profiles was not. These are necessary for stability and disruption analysis of the MAST database, as well as going forward for operation in the upgrade to the device, MAST…
Preprint PublishedM. Kong F. Felici O. Sauter C. Galperti T. Vu C. Ham T.C. Hender M. Maraschek M. Reich the TCV team the ASDEX Upgrade team the MAST team the EUROfusion MST1 team
This paper presents recent progress on the studies of neoclassical tearing modes (NTMs) on TCV, concerning the new physics learned and how this physics contributes to a better real-time (RT) control of NTMs. A simple technique that adds a small (sinusoidal) sweeping to the target electron cyclotron (EC) beam deposition location has proven effective…
Preprint PublishedJ.W. Berkery G. Xia J.M. Bialek S.A. Sabbagh Z.R. Wang C. Ham A. Thornton Y.Q. Liu
Assessment of the limits of stability of tokamak plasmas is key to operation in high fusion performance ranges without disruption of the plasma current. Projected equilibria have been generated for the MAST-U spherical tokamak experiment, an upgrade of the previous MAST device, in order to prepare for operation. These equilibria are scanned in p…
PreprintM J Dunn T W Morgan J W Genuit T Loewenhoff A J Thornton K J Gibson the Magnum-PSI team
One of the issues faced by future fusion devices will be high target heat loads. Alternative divertors are a potential solution to the heat loads. They have been investigated in TCV and DIII-D, and will be investigated on MAST-U. To evaluate their effectiveness, accurate target heat flux and power balance measurements are required in these machines…
Preprint PublishedA. Shepherd R. Akers A. Barth I.E. Day G. Fishpool R. McAdams R. Tivey R. Verhoeven
Neutral beam injection is one of the primary auxiliary heating systems for tokamak plasmas. Once the neutral beam leaves the neutraliser collisions with background neutral particles in the beamline and tokamak vessel re-ionises part of the neutral beam. These particles can be deflected by the tokamak magnetic field, potentially damaging unshielded …
Preprint PublishedG. J. McArdle L. Pangione M. Kochan
MAST has undergone a substantial upgrade [1], featuring among other things several new poloidal field coils mostly distributed around the new closed-throat divertor structure and an enlarged centre column. The considerable changes have required the plasma control software to be substantially re-written. The MAST digital plasma control system […
Preprint PublishedD A Ryan L Piron A Kirk Y Q Liu M Dunne L Li B Dudson W Suttrop the ASDEX Upgrade team the EUROfusion MST1 team
Edge Localised Modes (ELMs) in H-mode tokamak plasmas may be controlled or entirely suppressed by applying 3D magnetic perturbations (MPs). The applied perturbation is amplified by the plasma response, and it has previously been established that the size of the peeling component of this response is a reliable indicator for expected ELM control on A…
Preprint