I.T. Chapman E. de la Luna P.T. Lang Y. Liang B. Alper P. Denner D. Frigione L. Garzotti C.J. Ham G.T.A. Huijsmans S. Jachmich G. Kocsis M. Lennholm I. Lupelli F.G. Rimini A.C.C. Sips JET Contributors
ELM control may be essential to develop ITER scenarios with a reasonable lifetime of divertor components, whilst ELM pacing may be essential to develop stationary ITER scenarios with a tungsten divertor. Resonant magnetic perturbations (RMPs) have mitigated ELMs in high collisionality plasmas in JET. The efficacy of RMPs in mitigating the ELMs is f…
Preprint PublishedS. Pamela T. Eich L. Frassinetti B. Sieglin S. Saarelma G. Huijsmans M. Hoelzl M. Becoulet F. Orain S. Devaux I. Chapman I. Lupelli E. Solano JET Contributors
A subset of JET ITER-like wall (ILW) discharges, combining electron density and temperature as well as divertor heat flux measurements, has been collected for the validation of non-linear MHD simulations of Edge-Localised-Modes (ELMs). This permits a quantitative comparison of simulation results against experiments, which is required for the valida…
Preprint PublishedJ. Lovell G. Naylor A. Field P. Drewelow R. Sharples JET Contributors
A new resistive bolometer system has been developed for MAST-Upgrade. It will measure radiated power in the new Super-X divertor, with millisecond time resolution, along 16 vertical and 16 horizontal lines of sight. The system uses a Xilinx Zynq-7000 series Field-Programmable Gate Array (FPGA) in the D-TACQ ACQ2106 carrier to perform real time data…
Preprint PublishedM. J. Leyland M. N. A. Beurskens J. C. Flanagan L. Frassinetti K. J. Gibson M. Kempenaars M. Maslov R. Scannell JET Contributors
The Joint European Torus (JET) high resolution Thomson scattering (HRTS) system measures radial electron temperature and density profiles. One of the key capabilities of this diagnostic is measuring the steep pressure gradient, termed the pedestal, at the edge of JET plasmas. The pedestal is susceptible to limiting instabilities, such as Edge Local…
Preprint PublishedF. G. Rimini D. Alves G. Arnoux M. Baruzzo E. Belonohy I. Carvalho R. Felton E. Joffrin P. Lomas P. McCullen A. Neto I. Nunes C. Reux A. Stephen D. Valcarcel S. Wiesen JET EFDA contributors
The JET tokamak is unique amongst present fusion devices in its capability to operate at high plasma current, providing the closest plasma parameters to ITER. The physics benefits of high current operation have to be balanced against the risks to the integrity of the machine due to high force disruptions. The installation of the ITER-Like Wall (ILW…
Preprint PublishedR. McAdams A. Sparkes A. Ash I. Day D. King M. Kovari A. Shepherd I. Turner J. Zacks D. Ciric JET EFDA Contributors
In normal operation the JET neutral beam injectors have the operating gas supplied to the ion source and the neutraliser. For tritium operation the gas is supplied to both the ion source and neutraliser at a point close to the earth grid (grid gas) due to the difficulty in producing a gas line with a secondary containment and a ceramic break fo…
Preprint PublishedI.E. Day T.T.C. Jones JET EFDA Contributors
We describe the operational experience of the JET actively cooled duct liner and compare it with the previous inertially cooled duct. The paper discusses the initial conditioning of the duct liner during restart commissioning and subsequent high power performance. The new duct was conditioned in 48 plasma pulses during its first time commissioning …
Preprint PublishedA.D. Ash T.T.C. Jones E. Surrey D. Ciric S.I. Hall D. Young M. Afzal L. Hackett I.E. Day R. King JET EFDA Contributors
The JET Neutral Beam Injection (NBI) system is the most powerful neutral beam plasma heating system currently operating. Optical Interlocks were installed on the beam lines in 2011 for the JET Enhancement Project 2 (EP2), when the heating power was increased from 23 MW to 34 MW. JET NBI has two beam lines. Each has eight positive ion injectors oper…
Preprint PublishedD. Rendell S.R. Shaw P.J. Pool C. Oberlin-Harris JET EFDA Contributors
The JET flywheel generator converters have operated since 1983 and for over 85,000 pulses. Problems with this plant are discussed, including corrosion, unbalanced flow and arcing within the liquid resistors; starting difficulties on both machines; and failure of the plug-braking transformers at energisiation. In 2012/13 two sets of thrust bearing p…
Preprint PublishedX. Lefebvre A. Hollingsworth A. Parracho P. Dalgliesh B. Butler R. Smith JET EFDA Contributors
The aim of the Exhaust Detritiation System (EDS) of the JET Active Gas Handling System (AGHS) is to convert all Q-based species (Q2, Q-hydrocarbons) into Q2O (Q being indifferently H, D or T) which is then trapped on molecular sieve beds (MSB). Regenerating the saturated MSBs leads to the production of tritiated water which is stored in Briggs drum…
Preprint Published