J W Berkery S A Sabbagh C Ham V Zamkovska J Butt J Riquezes M Tobin S Henderson L Kogan B Patel R Scannell E Trier B LeBlanc
Fusion power output from spherical tokamaks would benefit from increased confined plasma density, but there exists a limit on the density before confinement is lost and the plasma current is disrupted. This density limit has long been characterized by a simple, global Greenwald limit proportional to the plasma current and inversely proportional …
Preprint PurchaseRuben Otin Wouter Tierens Felix Parra Shafa Aria Ernesto Lerche Philippe Jacquet Igor Monakhov Pierre Dumortie Bart Van Compernolle JET Contributors
When RF waves are applied in tokamaks with metal walls, sheath rectification effects associated with the fields induced in the scrape-off layer (SOL) may lead to enhanced plasma-wall interactions (i.e. heat-loads in the limiters, RF-induced impurity sources) which can endanger the integrity of the machine and limit the RF power. Although many co…
Preprint PublishedElla Fox-Widdows Mark D. Bowden Kazuo Hoshino Akiyoshi Hatayama Ryoko Osawa Yuka Tsubotani
Collisional-radiative models are commonly used to analyse atomic and molecular processes in low temperature plasmas by determining the distribution functions of excited states as functions of various plasma parameters. This paper outlines the improvements to a zero-dimensional collisional-radiative model, developed at Keio University, for purposes …
PreprintA. BreidiS. L. Dudarev
Thermal evolution and high temperature annealing of dislocation microstructure of an irradiated metal, described by an ensemble of in…
PublishedJames H.P. Rice Jianzhao Geng Rodney A. Badcock Dominic A. Moseley Steven Wray Heng Zhang
The application of dc magnetic field to a 2G high temperature superconducting (HTS) tape can reduce the critical current Ic of the tape, without driving the material normal. This property can be used in the development of HTS switching elements through so-called Jc(B) switching. The design of a dc magnetic field switch is reported, in both singl…
PreprintB. C. G. Reman R. O. Dendy T. Akiyama M. Salewski S. C. Chapman J. W. S. Cook H. Igami S. Inagaki K. Saito R. Seki G. S. Yun
During bursty MHD events, transient ion cyclotron emission (ICE) is observed from deuterium plasmas in the Large Helical Device (LHD) heliotron-stellarator. Unusually, the frequencies of the successive ICE spectral peaks are not close to integer multiples of the local cyclotron frequency of an energetic ion population in the likely emitting regi…
Preprint PublishedAndrew R. Warwick Max Boleininger Sergei L. Dudarev
Using atomistic simulations based on the creation-relaxation algorithm, we explore the evolution of microstructure in irradiated zirconium over a broad range of radiation exposure. In agreement with experimental observations, we find that at relatively low temperatures, microstructure evolves towards an asymptotic dynamic steady state forming at…
Preprint PublishedM. Brank R. A. Pitts G. Simič P. Lamalle M. Kocan F. Koechl Y. Gribov V. Polli L. Kos
Ion cyclotron resonance heating (ICRH) is one of the three additional heating schemes to be deployed on ITER. Its two antenna arrays, installed on the outboard midplane, will deliver 20 MW of RF power in the 40-55 MHz frequency range. The plasma-facing component of …
Preprint PurchaseM. Siccinio J. P. Graves R. Kembleton H. Lux F. Maviglia A. W. Morris J. Morris H. Zohm
This paper is part of a series of publications concerning the development of the European DEMO during the pre- conceptual design phase (2014-2020). In particular, it deals with the physics basis employed for the definition of the various DEMO baselines released, and …
Preprint PublishedViacheslav Kuksenko Artem Lunev Ed Darnbrough Chris Densham Patrick Hurh Steve Roberts
The effect of ion irradiation on evolution of microstructure and hardening of beryllium with different impurity levels was investigated using TEM and nanoindentation. High purity S-65 grade and less-pure S-200-F grade were implanted by helium ions at temperatures of 50°C and 200°C. 11 different energies were used, so as to create a quasi-homog…
Preprint Published