B. Geiger A. N. Karpushov S. Sharapov R. Akers A. Bock M. Dunne B. Duval M. Fontana L. Giannone J. Hobirk C. Hopf A.S. Jacobsen D. Keeling P. Lauber C. Marini P. ZS. Poloskei M. Salewski O. Sauter P. A. Schneider D. Testa A.J. Van Vuuren M. Willensdorfer TCV Team ASDEX Upgrade Team EUROfusion MST15 Team
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 …
PreprintS. S. Henderson M. Bernert C. Giroud D. Brida M. Cavedon P. David R. Dux J. R. Harrison A. Huber A. Kallenbach J. Karhunen B. Lomanowski G. Matthews A. Meigs R. A. Pitts F. Reimold M. L. Reinke S. Silburn N. Vianello S. Wiesen M. Wischmeier
While current tokamak experiments are beginning to utilise real-time feedback control systems to manage the plasma exhaust, future tokamaks still require validation of theoretical models used to predict the threshold impurity concentration required to facilitate stationary divertor operation. This work exploits new spectroscopic measurements of …
Preprint PublishedS.J. Freethy C. Lechte P. Rodriguez-Fernandez E. Fable T. Goerler G. Conway A.J. Creely T. Happel P. Hennequin A.E. White the ASDEX Upgrade team
The experimental validation of turbulence models is a critical part of developing a predictive understanding of plasma transport. Models based on the non-linear gyrokinetic equations are currently the most well understood and experimentally validated models of turbulence available. However, models of reduced complexity are required in order to mak…
Preprint PublishedM Valovič P T Lang A Kirk W Suttrop A Bock P J Mc Carthy M Faitsch B Plöckl2 the ASDEX Upgrade team the EUROfusion MST1 team
It is demonstrated that tokamak plasma can be fuelled by pellets while simultaneously maintaining ELM suppression by external resonant magnetic perturbations (RMPs). Pellets are injected from vertical high field site and deposited at outer part of plasma cross section. Each pellet triggers benign MHD event followed by short lived ELM free phase. Th…
Preprint PublishedW. Suttrop A. Kirk V. Bobkov M. Cavedon M. Dunne R.M. McDermott H. Meyer R. Nazikian C. Paz-Soldan D.A. Ryan E. Viezzer M. Willensdorfer The ASDEX Upgrade MST1 Teams
Access conditions for full suppression of edge localised modes (ELMs) by magnetic perturbations (MP) in low density high confinement mode (H-mode) plasmas are studied in the ASDEX Upgrade tokamak. The main empirical requirements for full ELM suppression in our experiments are: 1. The poloidal spectrum of the MP must be aligned for best plasma respo…
PublishedHendrik Meyer
The ASDEX Upgrade (AUG) programme is geared towards developing the physics basis for ITER and (EU)-DEMO and is jointly executed with the EUROfusion Medium Size Tokamak task force. Integrated scenario development to prepare future device operation, detailed physics studies to improve predictability of fusion devices and testing of fusion relevant t…
Preprint PublishedN. Zhang Y. Q. Liu P. Piovesan V. Igochine D. L. Yu S. Wang G. Q. Dong G. Z. Hao G. L. Xia W. J. Chen L. Liu J. Q. Li X. Bai
Resistive plasma response to the n = 1 (n is the toroidal mode number) RMP field is systematically investigated for a high-beta hybrid discharge on ASDEX Upgrade. Both linear and quasi-linear response are modelled using the MARS-F and MARS-Q codes, respectively. Linear response computations show a large internal kink response when the plasma centra…
Preprint PublishedN. Vianello D. Carralero C. K. Tsui V. Naulin M. Agostini J. Boedo B. Labit C. Theiler D. Aguiam S. Allan M. Bernert S. Costea I. Cziegler H. De Oliveira J. Galdon-Quiroga G. Grenfell A. Hakola C. Ionita H. Isliker A. Karpushov J. Kovacic B. Lipschultz R. Mauriozio K. McClements F. Militello J. Olsen J. J. Rasmussen T. Ravensbergen H. Reimerdes B. Schneider R. Schrittwieser M. Spolaore K. Verhaegh J. Vicente N. Walkden W. Zhang E. Wolfrum the ASDEX Upgrade Team the TCV team the EUROfusion MST1 Team
A detailed cross-device investigation on the role of filamentary dynamics in high density regimes has been performed within the EUROfusion framework comparing ASDEX-Upgrade (AUG) and TCV tokamaks. Both devices have run density ramp experiments at different levels of plasma current, keeping toroidal field or q95 constant in order to disentangle the …
Preprint PublishedS. S. Henderson M. Bernert S. Brezinsek M. Carr M. Cavedon R. Dux D. S. Gahle J. Harrison B. Lipschultz B. Lomanowski A. Meigs M. O’Mullane F. Reimold M. L. Reinke S. Wiesen the EUROfusion MST1 team the ASDEX Upgrade team JET contributors
Reducing the plasma power exhaust impacting on plasma facing components during steady state operation is one of the major design issues in future tokamaks such as ITER. Impurity seeding, e.g. with N, is one method of achieving this and has been used for a long time in tokamak research [1]. In this work we exploit a recently developed spectroscopic …
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…
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