K. D. Lawson K. M. Aggarwal I. H. Coffey F. P. Keenan R. H. G. Reid et al.
The VUV/XUV spectral region is particularly rich in lines emitted by plasmas with temperatures = 30 keV used in fusion research. Examples are presented of analyses of JET tokamak data involving C VUV/XUV radiation. In the first, the C IV divertor emission is modelled, with agreement between theory and experiment to within the measurement accuracy o…
PublishedI.T. Chapman A. Kirk S. Saarelma J.R. Harrison R. Scannell The Mast Team
The application of resonant magnetic perturbations with toroidal mode number n = 4 or n = 6 is observed to result in a significant increase in ELM frequency, despite a reduction in the edge pressure gradient. A picture for how type-I ELMs are mitigated, or destabilised, when magnetic perturbations are applied is proposed. Despite the magnetic pertu…
PublishedR. Mcadams D. B. King A. J. T. Holmes E. Surrey
In fusion negative ion sources, the negative ions are formed on the caesiated plasma grid predominantly by hydrogen atoms from the plasma. The space charge of the negative ions leaving the wall is not fully compensated by incoming positive ions and at high enough emission a virtual cathode is formed. This virtual cathode limits the flux of negative…
PublishedH. P. Summers N. R. Badnell A. R. Foster A. Giunta F. Guzmán et al.
The paper is a tribute to Nicol Peacock and has a focus on interests and developments at Culham Laboratory from ~ 1970 when Nicol led the UKAEA spectroscopy team. The paper charts a little of the evolution of these models and their data through the seventies and eighties on into this century at Culham. The paper concludes with the state of efforts …
PublishedI.T. Chapman R.J. La Haye R.J. Buttery W.W. Heidbrink G.L. Jackson C.M. Muscatello C.C. Petty R.I. Pinsker B.J. Tobias F. Turco
Sawtooth control using electron cyclotron current drive (ECCD) has been demonstrated in ITER-like plasmas with a large fast ion fraction, wide q = 1 radius and long uncontrolled sawtooth period in DIII-D. The sawtooth period is minimized when the ECCD resonance is just inside the q = 1 surface. Sawtooth destabilization using driven current inside q…
PublishedM. Nocente M. Angelone P. Blanchard C. Cazzaniga I. Chugunov et al.
A system based on a LaBr 3 (Ce) scintillator and digital data acquisition is discussed in view of γ-ray spectroscopy measurements on a fusion burning plasma. High energy resolution and high rate capability of the system are demonstrated in laboratory tests and in dedicated experiments at nuclear accelerators. Preliminary results on sensitivity of …
PublishedM Valovic G Cunningham L Garzotti C Gurl A Kirk G Naylor A Patel R Scannell The Mast Team
Shallow fuelling pellets are injected from the high field side into plasmas in which ELMs have been mitigated using external magnetic perturbation coils. The data are compared with ideal assumptions in the ITER fuelling model, namely that mitigated ELMs are not affected by fuelling pellets. Firstly it is shown that during the pellet evaporation an …
PublishedA. Kirk I.T. Chapman J. Harrison Yueqiang Liu E. Nardon S. Saarelma R. Scannell A.J. Thornton The Mast Team
The application of resonant magnetic perturbations (RMPs) with a toroidal mode number of n=4 or n=6 to lower single null plasmas in the MAST tokamak produces up to a factor of 5 increase in Edge Localized Mode (ELM) frequency and reduction in plasma energy loss associated with type-I ELMs. A threshold current for ELM mitigation is observed above wh…
Published