C. 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…
PreprintJ P Coad M Rubel J Likonen N Bekris S Brezinsek G F Matthews M Mayer A M Widdowson JET contributors
The first divertor was installed in the JET machine between 1992 and 1994 and was operated with carbon tiles and then beryllium tiles in 1994-5. Post-mortem studies after these first experiments demonstrated that most of the impurities deposited in the divertor originate in the main chamber, and that asymmetric deposition patterns generally favouri…
Preprint PublishedJ. P. Coad M. Rubel J. Likonen N. Bekris S. Brezinsek G. F. Matthews M. Mayer A. M. Widdowson JET contributors
The first divertor was installed in the JET machine between 1992 and 1994 and was operated with carbon tiles and then beryllium tiles in 1994–5. Post-mortem studies after these first experiments demonstrated that most of the impurities deposited in the divertor originate in the main chamber, and that asymmetric deposition patterns generally favou…
PublishedC. Giroud N. Aiba F. Militello C. Challis A. Chankin B. Lomanowski D. Hatch J. Harrison D. Frigione D. Moulton S. Pamela F. Parra J. Parisi I. Putzai D. Refy S. Saarelma C. Stavrou B. Tal E. Belonohy S. Brezinsek S. Buller C. Bowman E. Delabie A. Field J. Fontdecaba A. Huber A. Meigs S. Menmuir J. Simpson JET Contributors
Preprint Published
C.D. Challis S. Brezinsek I. Coffey M. Fontana N. Hawkes D. Keeling D. King G. Pucella E. Viezzer JET Contributors
The initial current ramp phase of JET hybrid plasmas is used to optimise the target q-profile for main heating to allow access to high beta and avoid MHD instabilities. Mixed protium-deuterium experiments, carried out at JET since the installation of the beryllium-tungsten wall, have shown that the q-profile evolution during this Ohmic phase varies…
Preprint PublishedK D Lawson M Groth D Harting S Menmuir D Reiter K M Aggarwal S Brezinsek I H Coffey G Corrigan F P Keenan C F Maggi A G Meigs M G O’Mullane S Wiesen JET Contributors
An understanding of the plasma edge and divertor is essential for predicting the performance of next-step machines such as ITER. Transport codes used to study the divertor behaviour [1] employ atomic physics data in two applications. The first is to predict the power radiated by the fuel and impurity atoms, which is carried out as a post-processing…
Preprint PublishedC.D. Challis S. Brezinsek I. Coffey N. Hawkes D. Keeling D. King G. Pucella E. Viezzer JET Contributors
The initial Ohmic current ramp phase of JET hybrid plasmas, including a current ‘overshoot’ before the main heating, is used to optimise the q-profile shape to allow access to high β and avoid MHD instabilities [1]. Such hybrid plasmas have never been operated using tritium (T) or mixed deuterium-tritium (D-T) fuel. However, experiments with i…
Preprint PublishedS. S. Henderson M. Bernert S. Brezinsek M. Carr M. Cavedon R. Dux D. S. Gahle J. Harrison B. Lipschultz B. Lomanowski A. Meigs M. O’Mullane F. Reimold M. L. Reinke S. Wiesen the EUROfusion MST1 team the ASDEX Upgrade team JET contributors
Reducing the plasma power exhaust impacting on plasma facing components during steady state operation is one of the major design issues in future tokamaks such as ITER. Impurity seeding, e.g. with N, is one method of achieving this and has been used for a long time in tokamak research [1]. In this work we exploit a recently developed spectroscopic …
Preprint Published