J. 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…
PreprintK. Verhaegh B. Lipschultz J.R. Harrison B.P. Duval A. Fil D.S. Gahle D. Moulton O. Myatra A. Perek S. Henderson C. Theiler A. Thornton M. Wensing
This paper shows experimental results from the TCV tokamak that indicate plasma-molecule interactions involving D+2 and possibly D− play an important role as sinks of energy (through hydrogenic radiation as well as dissociation) and particles during divertor detachment if low target temperatures (< 3 eV) are achieved. Bot…
Preprint PublishedKevin Verhaegh Basil Duval Ben Dudson Alex Fil Olivier Février Daljeet Gahle James Harrison Omkar Myatra Artur Perek Christian Theiler Mirko Wensing
In this work we provide experimental insights into the impact of plasma-molecule interactions on divertor detachment by applying new spectroscopic analysis techniques to the hydrogen Balmer line series to investigate how both atom and plasma-molecule interactions impact particle balance. Our analysis on a representative L-mode TCV density ramp dis…
Preprint PublishedH. J. Sun RJ. Goldston A.Huber XQ. Xu J. Flanagan DC. McDonald E. de la Luna M. Maslov J. Harrison F. Militello J. Fessy S. Cramp JET Contributors
A study of a dataset of JET plasma with the Be/W ITER-like wall (JET-ILW) shows that reaching the edge MHD ballooning limit leads to confinement degradation. However, unlike JET plasma with a carbon wall (JET-C), the JET-ILW plasma stays in a marginal dithering phase for a relatively long period, associated with a higher a ( 20%) H-mode density lim…
Preprint PublishedJ. S Allcock S. A. Silburn R. M. Sharples J .R. Harrison N. J. Conway J. W. M. Vernimmen
In this paper, the pixelated phase mask (PPM) method of interferometry is applied to coherence imag-ing (CI) — a family of passive, narrowband spectro-polarimetric imaging techniques for diagnosing plasmas. Compared to designs using a linear phase mask, PPM is more compact, rugged and has a higher spatial resolution (averaged across both image…
Preprint PublishedK. Verhaegh B. Lipschultz C. Bowman B.P. Duval U. Fantz A. Fil D. Moulton O. Myatra D. Wünderlich F. Federici D.S. Gahle J.R. Harrison A. Perek M. Wensing
Detachment, an important mechanism for reducing target heat deposition, is achieved through reductions in power, particle and momentum; which are induced through plasma-atom and plasma-molecule interactions. Experimental research in how those reactions precisely contribute to detachment is limited. Both plasma-atom as well as plasma-molecule intera…
Preprint PublishedS. 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 PublishedC. Bowman J. R. Harrison B. Lipschultz S. Orchard K. J. Gibson M. Carr K. Verhaegh O. Myatra
Advancing our understanding of divertor plasma physics is limited by an inability to directly determine the plasma characteristics (density, temperature, etc) over the entire divertor cross-section. At best, diagnostics are able to measure ne and Te at isolated points. More commonly however, diagnostics only measure higher-level quantities (e.g. em…
Preprint PublishedC. Giroud N. Aiba F. Militello C. Challis A. Chankin B. Lomanowski D. Hatch J. Harrison D. Frigione D. Moulton S. Pamela F. Parra J. Parisi I. Putzai D. Refy S. Saarelma C. Stavrou B. Tal E. Belonohy S. Brezinsek S. Buller C. Bowman E. Delabie A. Field J. Fontdecaba A. Huber A. Meigs S. Menmuir J. Simpson JET Contributors
Preprint Published
J.E. Menard R. Majeski M. Ono N.N. Bakharev V.K. Gusev M. Gryaznevich D. Kingham S. McNamara P. Thomas K. Hanada J. Harrison B. Lloyd Y.S. Hwang B. Lipschultz H. Wilson Y. Nagayama Y. Ono Y. Takase M. Reinke K. Tobita Z. Gao F. Alladio R.J. Fonck
The spherical torus/tokamak (ST) is a potentially attractive configuration for narrowing scientific and technical gaps to a fusion demonstration power plant and as a more compact and/or modular fusion power source. Due to a reduced plasma surface area to volume ratio, the ST configuration offers the potential to access high power exhaust heat fl…
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