Vasili Kiptily F. Belli J. Eriksson C. Hellesen V.Goloborod’ko K.Schöpf
An effect due to fusion born triton production has been observed in JET high-performance deuterium plasma discharges with NBI and H-minority ICRF heating, using DD and DT neutron spectrometry as well as fusion product loss measurements. The observations show that increase of the triton burn up rate leads to decrease of second harmonic ωcH
Preprint PublishedM. Fitzgerald J. Buchanan S. E. Sharapov V. G. Kiptily M. Sertoli G. Szepesi J. Boom R. Akers D. King JET contributors
Fishbones are ubiquitous in high-performance JET plasmas and are typically considered to be unimportant for scenario design. However, during recent high-performance hybrid experiments, sporadic and explosive fishbones have been observed which correlate with a reduction in performance and main chamber hotspots. Clear evidence has been obtained of fu…
Preprint PublishedK. G. McClements A. Brisset B. Chapman S. C. Chapman R. O. Dendy P. Jacquet V. G. Kiptily M. Mantsinen B. C. G. Reman JET Contributors
Measurements are reported of electromagnetic emission close to the cyclotron frequency of energetic ions in JET plasmas heated by waves in the ion cylotron range of frequencies (ICRF). Hydrogen was the majority ion species in all of these plasmas. The measurements were obtained using a sub-harmonic arc detection (SHAD) system in the transmission li…
Preprint PublishedV. G. Kiptily M. Fitzgerald V. Goloborodko S. E. Sharapov C. D. Challis D. Frigione J. Graves M. J. Mantsinen P. Beaumont M. Garcia-Munoz C. Perez von Thun J. F. R. Rodriguez D. Darrow D. Keeling D. King K. G. McClements E. Solano S. Schmuck G. Sips G. Szepesi JET contributors
During development of a high-performance hybrid scenario for future deuterium–tritium experiments on the Joint European Torus, an increased level of fast ion losses in the MeV energy range was observed during the instability of high-frequency n = 1 fishbones. The fishbones are excited during deuterium neutral beam injection combined with…
Preprint PublishedV.G. Kiptily
Comparing with ITER, the experimental fusion machine under constraction, the next step test fusion power plant, DEMO will be characterized by very long pulse/steady-state operation and much higher plasma volume and fusion power. The substantially increased level of neutron and gamma fluxes will require reducing the physical access to the plant. It …
Preprint PublishedL. Giacomelli S. Conroy F. Belli G. Gorini E. Joffrin V. Kiptily E. Lerche A. Murari V.V. Plyusnin S. Popovichev C. Reux M. Riva D.B. Syme JET EFDA Contributors
The Joint European Torus (JET, Culham, UK) is the largest tokamak in the world. JET has been upgraded over the years and recently it has also become a test facility of the components designed for ITER, the next step fusion machine under construction in Cadarache (France). At JET, the neutron emission profile of Deuterium (D) or Deuterium-Tritium (D…
PublishedE. Lerche D. Van Eester Y. Kazakov P. Jacquet I. Monakhov M. Goniche L. Colas F. Rimini K. Crombé R. Dumont V. Kiptily M. Santala JET Contributors
Heating single ion species plasmas with ICRF is a challenging task: Fundamental ion cyclotron heating (w = w ci ) suffers from the adverse polarization of the RF electric fields near the majority cyclotron resonance while second harmonic heating (w = 2w ci ) typically requires pre-heating of the plasma ions to become efficient. Recently, w = 2w ci …
Preprint PublishedV. G. Kiptily P. Beaumont F. Belli F. E. Cecil S. Conroy T. Craciunescu M. Garcia-Munoz M. Curuia D. Darrow Et. Al.
JET equipped with ITER-like wall (a beryllium wall and a tungsten divertor) can provide auxiliary heating with power up to 35MW, producing a significant population of alpha-particles in DT operation. The direct measurements of alphas are very difficult and alpha-particle studies require a significant development of dedicated diagnostics. JET now ha…
PublishedD. Gin I. Chugunov A. Shevelev E. Khilkevitch D. Doinikov V. Naidenov A. Pasternak I. Polunovsky V. Kiptily
Gamma diagnostics is considered to be primary for the confined alpha-particles and runaway electrons measurements on ITER. The gamma spectrometer will be embedded into a neutron dump of the ITER Neutral Particle Analyzer diagnostic complex. It will supplement NPA measurements on the fuel isotope ratio and confined alphas/fast ions. In this paper an…
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