D.M.A.Taylor M.J.Mantsinen D.Gallart J.Manyer JET contributors
Using the PION ICRH modelling code on JET tokamak pulses, the effect of including pitch angle dependence within the RF diffusion operator is investigated. This is found to be of greatest importance to the particle distribution function in cases of higher harmonic heating and lower heating ion mass, resulting in faster drop-off of the distribution 
Preprint PublishedA J T HolmesR McAdams
A model is presented for space charge neutralisation of positive ion beams. The model is used for the particular case of the beams used for magnetic based fusion applications. The beams consist, after a gas neutraliser, of ions and atoms at different energies. Account is taken of the co…
Preprint PublishedN J Conway A Cackett C F Maggi A G Meigs K-D Zastrow T M Biewer D L Hillis
Since 2010, an in-vessel calibration light source (ICLS) has been used periodically on JET to calibrate a range of diagnostics at UV, visible and IR wavelengths. During shutdowns, the ICLS (essentially an integrating sphere) is positioned within the vacuum vessel by the remote handling (RH) system. Following the 2013 run, several changes were made …
Preprint PublishedS. Dowson S. Dorling H. K. Sheikh T. Blackman G. Jones A. Goodyear P. Puglia P. Blanchard A. Fasoli D. Testa N. Fil V. Aslanyan M. Porkolab W. Pires De Sa R. Galvao L. Ruchko J. Figueiredo C. Perez Von Thun JET Contributors
The Alfvén Eigenmode Active Diagnostic system (AEAD) has undergone a major upgrade and redesign to provide a state of the art excitation and real-time detection system for JET. The new system consists of individual 4kW amplifiers for each of the six antennas, allowing for increased current, separate excitation and real time control of relative …
Preprint PublishedD. Iglesias W. Arter I. Balboa P. Bunting C. Challis J.W. Coenen Y. Corre S. Esquembri S. Jachmich K. Krieger G.F. Matthews R.A. Pittsh V. Riccardo M.L. Richiusa M. Porton F. Rimini S. Silburn V.K. Thompson R. Otin D. Valcarcel L. Vitton-Mea Z. Vizvary J. Williams JET contributors
The JET outboard divertor targets are the in-vessel components which receive the largest heat flux density. Surface delamination, radial cracks, and tie rod failures have been observed in the outboard tungsten-coated CFC tiles, while bulk tungsten special lamellas were intentionally melted in dedicated experiments. These different types of damag…
PreprintR. B. Morales S. Heuraux R. Sabot S. Hacquin
All density profile reconstruction techniques for both O-mode and X-mode are based on the assumption that the cut-off frequency profile is monotonic. However, there are many sources of perturbations to the plasma that generate hollow areas in the cut-off frequency profile, breaking the aforementioned assumption. This causes a significant immediate …
Preprint PublishedJ. S. Edwards I. S. Carvalho R. Felton C. Hogben D. Karkinsky P. J. Lomas P. A. McCullen F. G. Rimini A. V. Stephen
The JET Real-Time Protection Sequencer (RTPS) co-ordinates responses for magnetic and kinetic actuators to protect the ITER-Like Wall from possible melting events and other undesirable scenarios. It allows programmable stop responses per pulse, based on alarms raised by other systems. The architecture combines a modular run-time application deve…
Preprint PublishedN. C. Hawkes E. Delabie S. Menmuir C. Giroud A. Meigs N. Conway T. M. Biewer D. L. Hillis
Charge-exchange spectroscopy on JET has become particularly challenging with the introduction of the ITER-like wall. The impurity spectra are weaker and contaminated by many tungsten lines. We have therefore upgraded the instrumentation to allow the simultaneous measurement of impurity and fuel-ion charge exchange by splitting the light between two…
Preprint PublishedMaria Lorena Richiusa Daniel Iglesias Guy F. Matthews Michael Porton Vaughan K. Thompson Zsolt Vizvary
The next D-T campaign will push JET ITER-like Wall (IWL) to high divertor power and energy levels. During the 2016 campaign, the Strike Point (SP) sweeping permitted relevant H-mode scenarios without exceeding the temperature limits imposed by JET Operation Instructions (JOIs). In the subsequent shutdown, six outer divertor tungsten-coated 2D carbo…
Preprint PublishedI. Turner R. McAdams W. Arter A. Ash M. Barnard D. Ciric I. Day D. Keeling D. King C. Lane M. Nicassio T. Robinson A. Shepherd J. Zacks
Increased neutralisation and hence injected neutral beam power can be achieved by increasing the neutraliser target. This has the potential to increase the loading on the ion source backplate due to backstreaming electrons. Measurements of the backplate power loading due to backstreaming electrons are presented for the JET EP2 neutral beam injector…
Preprint Published- 1
- 2