A. Ekedahl L. Delpech M. Goniche D. Guilhem J. Hillairet et al.
The aim of the Tore Supra tokamak is to address physics and technology issues of long pulse discharges. For this purpose, Tore Supra is equipped with two actively cooled Lower Hybrid Current Drive (LHCD) antennas (f = 3.7GHz), designed to operate in 1000s long pulses. One of these is the recently installed passive active multijunction (PAM) antenna…
PublishedR. Koch E. Lerche D. Van Eester M. Nightingale
A steady-state tokamak reactor (SSTR) requires a high efficiency current drive system, from plug to driven mega-amps. RF systems working in the ion-cyclotron range of frequencies (ICRF) have high efficiency from plug to antenna but a limited current drive (CD) efficiency and centrally peaked CD profiles. The latter feature is not adequate for a SST…
PublishedM.R. Gilbert S.L. Dudarev S. Zheng L.W. Packer J.-Ch. Sublet
In a fusion reactor, materials will be subjected to significant fluxes of high-energy neutrons. As well as causing radiation damage, the neutrons also initiate nuclear reactions leading to changes in the chemical composition of materials (transmutation). Many of these reactions produce gases, particularly helium, which cause additional swelling and…
PublishedAndrew Davis Andrew Turner
It is known that a priori information on the distribution of neutron fluxes over neutron transport models can improve the computational efficiency of Monte Carlo transport calculations via the use of variance reduction techniques. The uncertainty lies in finding a method which obtains this information as fast and effortlessly as possible. A number …
PublishedD. Dunai S. Zoletnik J. Sárközi A.R. Field
An avalanche photodiode based APD detector for the visible wavelength range was developed for low light level, high frequency beam emission spectroscopy BES experiments in fusion plasmas. This solid state detector has higher quantum efficiency than photomultiplier tubes, and unlike normal photodiodes, it has internal gain. This paper describes the …
PublishedP Tamain A Kirk E Nardon B Dudson B Hnat The Mast Team
The impact of Resonant Magnetic Perturbations (RMPs) on the edge of MAST L-mode plasmas is studied using a mid-plane reciprocating probe equipped with a Gundestrup probe head. A strong impact on the characteristics of the ion saturation current fluctuations is observed just inside the separatrix, with a broadening of the power spectrum and an asymm…
PublishedAndrea Murari Guido Vagliasindi Sebastiano De Fiore Eleonora Arena Paolo Arena Luigi Fortuna Y. Andrew M. Johnson JET-EFDA Contributors
Dynamical systems are often considered immune from memory effects, i.e., the dependence of their time evolution on the previous history. This assumption has been tested for two phenomena in nuclear fusion that are believed to sometimes show sensitivity to the previous history of the discharge: disruptions and the transition from the L mode to the H…
PublishedJ. Mlynar V. Weinzettl G. Bonheure A. Murari JET-EFDA Contributors
Several diagnostic systems in magnetically confined fusion plasmas provide line-integrated measurements along chords, including bolometry, visible light, soft-Xray ~SXR!, or neutron diagnostics. The task of retrieval of spatial distribution of the plasma emissivity from the line-integrated measurements constitutes an important part of fusion data a…
PublishedD.J. Ward
Conceptions of the aims and characteristics of DEMOs are evolving in response to world issues. Many areas are important in these considerations: two particularly important, and technically related, ones are examined here. Firstly, in the recent Strategic Energy Technology plan (SET plan) in the EU, approaches to technological development that could…
Published