I. Balboa E. Rose G. F. Matthews D. Croft M. Stamp S. A. Silburn J. C. Williams D. Hepple A. Huber S. Whetham D. Iglesias D. J. Kinna M. Beldishevski J. Figueiredo C. Perez Von Thun G. Jones N. Balshaw L. D. Horton R. C. Lobel I. J. Pearson K. W. Pepperell G. Fishpool B. Lane K-D. Zastrow G. Arnoux G. Bodnar P. Carman N. J. Conway N. Gupta V. Huber G. Kocsis A. Manzanares C. Ruiz de Galarreta C. Marren R. Otín J. Naish V. K. Thompson JET Contributors
This article starts with a brief description of two new viewing systems with a light path which crosses the biological shield wall and are compatible with Deuterium-Tritium (D-T) operations in JET. However, it focuses on the optical modelling and engineering design of one of them which is a multiple camera system producing a wide angle view (WAV)…
Preprint PurchaseI. Balboa E. Rose G. F. Matthews D. Croft M. Stamp S. A. Silburn J. C. Williams D. Hepple A. Huber S. Whetham D. Iglesias D. J. Kinna M. Beldishevski J. Figueiredo C. Perez Von Thun N. Balshaw L. D. Horton R. C. Lobel I. J. Pearson K. W. Pepperell G. Fishpool B. Lane K-D. Zastrow G. Arnoux G. Bodnar P. Carman P. Carvalho N. J. Conway V. Huber J. Karhunen G. Kocsis A. Manzanares P. Puglia C. Ruiz de Galarreta C. Marren R. Otín J. Naish V. K. Thompson the JET Contributors*
Following from the paper describing the remote wide angle viewing system compatible with Deuterium-Tritium operations. This is the second article describing a second remote line of sight, this time focusing on the imaging of the divertor region in JET. It explains in detail the optical and engineering designs of constructing an optical relay which …
Preprint PublishedM. Kong E. Nardon M. Hoelzl D. Bonfiglio D. Hu U. Sheikh A. Boboc P. Carvalho T.C. Hender S. Jachmich K.D. Lawson S. Silburn Ž. Štancar R. Sweeney G. Szepesi the JOREK team JET contributors
Shattered pellet injection (SPI), with research started in recent years, is the current concept for the ITER disruption mitigation system (DMS) to prevent disruption-related damage. Compared with impurity SPI, pure deuterium (D2) SPI could contribute to runaway electron (RE) avoidance in ITER via a strong dilution cooling before the thermal quen…
PreprintHJ. Sun SA. Silburn IS. Carvalho C Giroud G Fishpool GF. Matthews DB. King RB. Henriques DL. Keeling FG. Rimini L. Garzotti D. Frigione D. Van Eester D Kos M-L. Mayoral J. Mailloux C. Maggi A. Huber D. Douai PJ. Lomas L Morten M. Maslov K. Kirov P. Jacquet CG. Lowry M. Baruzzo C. Stuart J. Mitchell L. Horvath DC. McDonald JET Contributors
Unusually high power loads on the Beryllium limiter caused by Neutral Beam re-ionisation, and much cooler divertor target surfaces were observed during the recent JET tritium campaign. As both phenomena are driven by scrape-off layer (SOL) physics, the SOL features of 72 tritium H-mode discharges and their deuterium references have been studied. …
Preprint PublishedC. Giroud S. Brezinsek R. Pitts I.S. Carvalho A. Huber E. Kaveeva D. Keeling J. Mailloux S. Aleiferis B. Chapman S. Henderson L. Garzotti E. Lerche M. MArin M. Maslov M. Brix P. Carvalho I. Coffey J. Fontdecaba L. Horvath I. Jepu J. Karhunen E. Litherland-Smith A. Meigs R.B. Morales T. Pereira D. Refy Z. Stancar M. Sertoli S. Silburn G. Szepesi A. Thorman M. Tomes I. Veselova B. Viola S. Wiesen JET contributors,
JET has investigated one the key issues for the baseline scenario in ITER, the integration of a radiative divertor for heat load control with the use of neon and nitrogen as seed impurity. A characterization of the choice of the impurity seed on plasma confinement, neutrons, pedestal MHD stability, pedestal instabilities, core transport is given…
PreprintS.N. Gerasimov P. Abreu L.R. Baylor A. Boboc I.S. Carvalho I.H. Coffey D. Craven V. Huber S. Jachmich E. Joffrin U. Kruezi M. Lehnen P.J. Lomas A. Manzanares M. Maslov E. Matveeva G. Pautasso A. Peacock S. Silburn C. Stuart H. Sun D. Shiraki R. Sweeney J. Wilson L.E. Zakharov
The disruption mitigation system at ITER will include four shattered pellet injectors (SPI), which will be dedicated to the mitigation of electro-magnetic loads (EML), thermal loads and the avoidance and suppression of runaway electrons. Recently the JETILW was equipped with an SPI with a wide capability. Specifically: pellet diameter d = [4.57, 8.…
PreprintJ. S Allcock S. A. Silburn R. M. Sharples J .R. Harrison N. J. Conway J. W. M. Vernimmen
In this paper, the pixelated phase mask (PPM) method of interferometry is applied to coherence imag-ing (CI) — a family of passive, narrowband spectro-polarimetric imaging techniques for diagnosing plasmas. Compared to designs using a linear phase mask, PPM is more compact, rugged and has a higher spatial resolution (averaged across both image…
Preprint PublishedC. Cowley P. Fuller Y. Andrew L. James L. Simons M. Sertoli S. Silburn A. Widdowson JET contributors
A robust impurity detection and tracking code, able to generate large sets of dust tracks from tokamak camera footage, is presented. This machine learning–based code is tested with cameras from the Joint European Torus, Doublet-III-D, and Magnum-PSI and is able to generate dust tracks with a 65–100% classification accuracy. Moreover, the number…
PublishedS. S. Henderson M. Bernert C. Giroud D. Brida M. Cavedon P. David R. Dux J. R. Harrison A. Huber A. Kallenbach J. Karhunen B. Lomanowski G. Matthews A. Meigs R. A. Pitts F. Reimold M. L. Reinke S. Silburn N. Vianello S. Wiesen M. Wischmeier
While current tokamak experiments are beginning to utilise real-time feedback control systems to manage the plasma exhaust, future tokamaks still require validation of theoretical models used to predict the threshold impurity concentration required to facilitate stationary divertor operation. This work exploits new spectroscopic measurements of …
Preprint PublishedT. Long J.S. Allcock L. Nie R. M. Sharples M. Xu R. Ke S. Zhang S. A. Silburn J. Howard B. Yuan Y. Yu Z.H. Wang X.M. Song L. Liu
A Doppler coherence imaging spectroscopy diagnostic has been developed on the HL- 2A tokamak for scrape-off-layer impurity plasma flow measurements. Two- dimensional imaging of line-averaged C2+ flow in the high-field-side scrape off layer with time resolution up to 1 ms, has been achieved successfully by this system. The spatial angular resolut…
Preprint Published