H. J. Sun E. Wolfrum T. Eich A. Kallenbach P. Schneider B. Kurzan U. Stroth the ASDEX Upgrade Team
A survey of the correlation between temperature and density gradient lengths ( and ) has been performed for the near SOL regions in the ASDEX Upgrade tokamak. In common with previous studies, the near SOL temperature and density gradient length ratio, , is found to be close to unity across a wide range of plasmas. However, it is found that it is po…
Preprint PublishedW.G. Fuller S. Allan B. Hnat N.R. Walkden
With MAST-U’s first plasma achieved in November 2020 and one of the key aims of the first experimental programme being to study exhaust physics, there is strong motivation to develop a new probe designed specifically for studying edge turbulence effects in the exhaust region of MAST-U. To create a new versatile probe, the design will be valida…
PreprintJ. Naish P. Batistoni B. Kros B. Obryk R. Villari JET contributors
In 2019 JET carried out a very successful Deuterium-Deuterium campaign, referred to as C38, producing a total of 3.751019 DD neutrons. During this campaign, a series of experiments were implemented to record the neutron fluence at positions close and far from the source and along shielding penetrations. Measurements were performed usi…
PreprintB Chapman R O Dendy S C Chapman K G McClements R Ochoukov
Observations have recently been made of ion cyclotron emission (ICE) that originates from the core plasma in the DIII-D and ASDEX-Upgrade tokamaks. In some of these cases, the ICE spectral peaks correspond to the local cyclotron harmonic frequencies of fusion-born ions close to the magnetic axis. This is in contrast to the hitherto usual spatial lo…
PreprintN. Mantel D. Bowden S.S. Herashchenko M. Fursdon A. D. L. Hancock I.E. Garkusha J. Roberts V.A. Makhlai A. von Mueller T. R. Barrett J.-H. You
In the conceptual design of EU-DEMO, damage to plasma facing components under disruption events is planned to be mitigated by specific sacrificial limiter components. A new limiter concept has been proposed using lattice structures fabricated with tungsten powder by additive manufacturing techniques. The major potential benefits of using a latti…
PublishedJ.W. Berkery S.A. Sabbagh J. Bialek
Disruption prediction and avoidance is necessary in future MAST-U spherical tokamak discharges to enable long-pulse plasma operation. Research examining the stability of plasmas in the MAST database utilizing proposed high quality kinetic equilibrium reconstructions and calculations with various codes, including the Disruption Event Characterizatio…
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 PublishedMikhail Yu. Lavrentiev Chu-Chun Fu Frédéric Soisson
We report a theoretical study of microstructure, magnetic properties, and their relationship in relatively concentrated Fe-Cr alloys in both Fe- and Cr-rich regions. Annealing of initially random systems at 500° C for times of the order of 106 s substantially changes their microstructure. In both systems, solute atoms form clusters with…
Preprint PublishedB Chapman R O Dendy S C Chapman L Holland S W A Irvine and B C G Reman
Observations have recently been made of ion cyclotron emission (ICE) that originates from the core plasma in the DIII-D [1, 2] and ASDEX-Upgrade [3, 4] tokamaks. The ICE spectral peaks correspond to the local cyclotron harmonic frequencies of fusion-born ions close to the magnetic axis, in contrast to the hitherto usual spatial localisation of …
Preprint PublishedR.G. Abernethy J.S.K.-L. Gibson A. Giannattasio J.D. Murphy O. Wouters S. Bradnam L.W. Packer M.R. Gilbert M. Klimenkov M. Rieth H.-C. Schneider C.D. Hardie S.G. Roberts D.E.J. Armstrong
Only limited data exist on the effect of neutron irradiation on the brittle to ductile transition (BDT) in tungsten. This work investigates the increase in brittle to ductile transition temperature (BDTT) following neutron irradiation to 1.67 displacements per atom, using four-point bend tests over a range of temperatures (623 – 1173 K) and strai…
Preprint Published