Michael Komm Stuart Henderson Sarah Elmore COMPASS team EUROfusion MST1 team
Partial detachment is the desired regime for the baseline burning plasma scenario in ITER and next-step devices, as it allows to disspate the majority of the energy carried by charged particles through the scrape-off-layer (SOL) and thus avoids localised heat flux deposition in the divertor region. The COMPASS tokamak is equipped with an open diver…
Preprint PublishedB D Dudson J Allen T Body B Chapman C Lau L Townley D Moulton J Harrison B Lipschultz
A new 1D divertor plasma code, SD1D, has been used to examine the role of recombination, radiation, and momentum exchange in detachment. Neither momentum or power losses by themselves are found to be sufficient to produce target ion flux rollover in detachment; radiative power losses are required to a) limit and reduce the ionization source and …
Preprint PublishedK.G. McClements
Detailed in situ studies of magnetic reconnection and particle acceleration, which play a crucial role in the release and redistribution of energy in solar flares, can be performed in tokamak plasmas under conditions resembling those of the flaring solar corona. Recent measurements and modelling of fast particle production during reconnection event…
Preprint PublishedA. Davis J. Barzilla A. Ferrari K. T. Lee V. Vlachoudis P. P. H. Wilson
As part of the expansion of the Direct Accelerated Geometry Monte Carlo (DAGMC) toolkit to support other Monte Carlo codes, FluDAG (FLUKA integrated with DAGMC) was developed. There has been increasing demand from the high energy physics community regarding Computer Aided Design (CAD) geometry support in Monte Carlo codes. In this paper, the develo…
Preprint PublishedR. Darkins D. M. Duffy P.-W. Ma S. T. Murphy
Ultrafast irradiation can drive the electrons in a material out of thermal equilibrium with the nuclei, producing hot, transient electronic states that modify the interatomic potential energy surface. We present, for the first time, a rigorous formulation of two-temperature molecular dynamics that can accommodate these electronic effects in the fo…
Preprint PublishedD. Moulton G. Corrigan J.R. Harrison B. Lipschultz JET Contributors
This paper further analyses the EDGE2D-EIRENE simulations presented by [Chankin et al (2017 Nucl. Mater. Energy 12 273], of L-mode JET plasmas in vertical-vertical (VV) and vertical-horizontal (VH) divertor configurations. As expected, the simulated outer divertor ionisation source peaks near the separatrix in VV …
Preprint PublishedS. S. Henderson M. M. Bluteau M. G. O’Mullane H. P. Summers
Spectra line power by medium and heavy weight elements is a main source of radiative loss in tokamak plasma and sets operational limits on the design of ITER and DEMO. The preferred comprehensive basis of impurity line power coefficients provided by ADAS is theoretical, using the Autostructure code with distorted wave electron impact cross-sections…
PreprintM. Fitzgerald J. Buchanan S. E. Sharapov V. G. Kiptily M. Sertoli G. Szepesi J. Boom R. Akers D. King JET contributors
Fishbones are ubiquitous in high-performance JET plasmas and are typically considered to be unimportant for scenario design. However, during recent high-performance hybrid experiments, sporadic and explosive fishbones have been observed which correlate with a reduction in performance and main chamber hotspots. Clear evidence has been obtained of fu…
Preprint PublishedL. Garzotti P. Belo G. Corrigan D. Harting F. Köchl A. Loarte E. Militello Asp V. Parail R.Ambrosino M. Cavinato M. Mattei M. Romanelli R. Sartori M. Valovič
The operation of a tokamak designed to test the sustainability of a thermonuclear grade plasma like the International Tokamak Experimental Reactor (ITER) presents several challenges. Among them is the necessity of fuelling the plasma to reach the density required to generate enough fusion power to achieve Q = 10 and, at the same time, to protect th…
Preprint PublishedB. Chapman R. O. Dendy S. C. Chapman K. G. McClements G. S. Yun S. G. Thatipamula M. H. Kim
Chirping observed in ion cyclotron emission (ICE) from the KSTAR tokamak at sequential proton harmonics in the range 200 to 500 MHz has recently been interpreted (B. Chapman et al., Nucl. Fusion 57, 124004 (2017)) as due to fast, sub-microsecond, evolution of the local deuterium plasma density. This density evolution changes the plasma environment …
Preprint Published