M. 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…
PreprintM. VALOVIČ Y. BARANOV A. BOBOC J. BUCHANAN J. CITRIN E. DELABIE L. GARZOTTI C. GIROUD R. MCKEAN E. LERCHE E. DE LA LUNA V. KIPTILY F. KÖCHL M. MARIN S. MENMUIR C. VON THUN G. TVALASHVILI AND THE JET CONTRIBUTORS
Control of plasma H:D isotope mix using solely shallow pellets (in H or D) was demonstrated in recent experiments, attaining ~50%:50% ratio. The isotope mix propagates from the edge to the core on the confinement timescale. Isotope dependence of energy confinement is within error bar to scaling laws. A dataset is collected for different pellet s…
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.…
PreprintAl Boboc P. Trimble G. Jones J. Fessey S. Cramp W. Studholme
We report on the selection, implementation and successful demonstration of a new automated laser control system for JET’s Far Infrared Interferometer, a diagnostic essential for machine protection. The new control system allows all laser subsystems and sensors to be interlocked and operated remotely in a precise and preprogramed manner, functiona…
Preprint PublishedL. Horvath C.F. Maggi A. Chankin S. Saarelma A.R. Field E. Belonohy A. Boboc G. Corrigan E.G. Delabie J. Flanagan L. Frassinetti C. Giroud D. Harting D. Keeling D. King M. Maslov G.F. Matthews S. Menmuir S.A. Silburn J. Simpson A.C.C Sips H. Weisen K.J. Gibson JET Contributors
The pedestal structure, ELM losses and linear MHD stability are analysed in a series of JET-ILW H and D type I ELMy H-mode plasmas. The pedestal pressure (pPED) is typically higher in D than in H at the same input power, with the difference mainly due to lower density in H than in D. At the same input power, the pedestal electron pres…
Preprint PublishedM. Maslov A. Boboc M. Brix J. Flanagan M. Romanelli C. Price JET contributors
This work describes the behaviour of the global energy and particle confinement on JET observed in a massive database of H-mode plasmas covering almost whole lifetime of JET operations, both with carbon and metal wall. The analysis is focused on type I ELMy H-modes in stationary phases. It is shown that plasma density in that regime is determined m…
Preprint PublishedA. Boboc B. Bieg R. Felton S. Dalley Yu. Kravtsov
In this paper, we present the work in the implementation of a new calibration for the JET real-time polarimeter based on the complex amplitude ratio technique and a new self-validation mechanism of data. This allowed easy integration of the polarimetry measurements into the JET plasma density control (gas feedback control) and as well as machine pr…
Preprint PublishedM. Gelfusa A. Murari P. Gaudio A. Boboc M. Brombin F. P. Orsitto E. Giovannozzi JET EFDA Contributors
An equivalent model of JET polarimeter is presented, which overcomes the drawbacks of previous versions of the fitting procedures used to provide calibrated results. First of all the signal processing electronics has been simulated, to confirm that it is still working within the original specifications. Then the effective optical path of both the v…
PublishedOliver Ford J. Svensson A. Boboc D. C. Mcdonald JET-EFDA Contributors
An analytical Bayesian inversion of the JET interferometry line integrated densities into density profiles and associated uncertainty information, is demonstrated. These are used, with a detailed model of plasma polarimetry, to predict the rotation and ellipticity for the JET polarimeter. This includes the lateral channels, for over 45,000 time poi…
PublishedA. Murari L. Zabeo A. Boboc D. Mazon M. Riva
Optical interferometers are normally used in magnetically confined plasmas to measure the refractive index of the plasma by comparing the phase shift variation between a reference and a probe laser beam, from which the line-integrated electron density can be derived. Unfortunately, interferometric measurements are affected by fringe jumps, which ar…
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