-
UKAEA-CCFE-PR(18)812018
Fast ion synergistic effects were studied by predictive modelling of JET best performing pulses for various levels of Neutral Beam (NB) and Radio Frequency (RF) power. Calculated DD neutron yields were analysed with the intention of separating the impact of sheer synergistic effects due to changes in fast ion (FI) distribution function (DF) from su…
-
UKAEA-CCFE-PR(18)132018
For the first time, over five confinement times, the self-consistent flux driven time evolution of heat, momentum transport and particle fluxes of electrons and multiple ions including Tungsten (W) is modeled within the integrated modeling platform JETTO [Romanelli M et al PFR 2014], using first principle-based codes : namely, QuaLiKiz [Bourd…
-
CCFE-PR(15)1092015
Start-up technique reported here relies on a double mode conversion (MC) for electron Bernstein wave (EBW) excitation. It consists of MC of the ordinary (0) mode, entering the plasma from the low field side of the tokamak, into the extraordinary (X) mode at a mirror-polarizer located at the high field side. The X mode propagates back to the plasma,…
-
2014
An overview of the recent results of Lower Hybrid (LH) experiments at JET with the ITER-like wall (ILW) is presented. Topics relevant to LH wave coupling are addressed as well as issues related to ILW and LH system protections. LH wave coupling was studied in conditions determined by ILW recycling and operational constraints. It was concluded that …
-
2013
In this paper important aspects of Lower Hybrid (LH) operation with the ITER Like Wall (ILW) [1] at JET are reported. Impurity release during LH operation was investigated and it was found that there is no significant Be increase with LH power. Concentration of W was analysed in more detail and it was concluded that LH contributes negligibly to its…
-
2011
Lower Hybrid waves have shown to have a high current drive (CD) efficiency suitable for current profile modification [1, 2]. These results were obtained at rather low density. Recent results on C-Mod [3], FTU [4] and JET [5, 6] indicate that CD efficiency could decrease at high density. On JET, the analysis of the contribution of fast electrons to …
-
2011
Mechanisms of arc formation have been analyzed and the critical electric fields for the multipactor effect calculated, compared to the experimental values and found to be within the normal operational space of the LH system on JET. It has been shown that the characteristic electron energy (20-1000)eV for the highest multipactor resonances (N=4-9) a…
-
2009
In this paper, significant results in the heating and current drive domains obtained at JET in the past few years following systems upgrade and dedicated experimental time, will be reviewed. Firstly, an overview of the new Ion Cyclotron Resonance Frequency (ICRF) heating capabilities will be presented i.e. results trom the ITER-Like ICRF antenna (I…
-
2009
The new Oblique ECE diagnostics of JET allows simultaneous measurement along three lines of sight at different toroidal angles. JET pulses, in which modulated LHCD power was applied, were analyzed by means of the SPECE emission code, which takes into account the fast electron tail generated by LH. The code results were compared to the ECE spectra f…
-
2009
During high power commissioning of the JET LH launcher, the radiation and impurity release has been analyzed from various diagnostics: VUV and visible spectroscopy, bolometry. These two last diagnostics have lines-of-sight viewing the launcher and can provide information about the electron and/or impurity source localisation. Using a database of 80…
Showing 11 - 20 of 25 UKAEA Paper Results