New developments in the diagnostics for the fusion products on JET in preparation for ITER (invited)

Journal Article · Fri Oct 15 00:00:00 EDT 2010 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.3502038· OSTI ID:22058722

Murari, A; Angelone, M; Pillon, M ^[1]; Bonheure, G ^[1]; Cecil, E ^[1]; Craciunescu, T; Zoita, V L ^[1]; Darrow, D ^[1]; Edlington, T; Kiptily, V; Popovichev, S; Syme, B ^[1]; Ericsson, G; Gatu-Johnson, M; Hellesen, C ^[1]; Gorini, G; Tardocchi, M ^[1]; Mlynar, J ^[1]; Perez von Thun, C ^[1]

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1. JET-EFDA, Culham Science Centre, OX14 3DB, Abingdon (United Kingdom)

Notwithstanding the advances of the past decades, significant developments are still needed to satisfactorily diagnose ''burning plasmas.'' D-T plasmas indeed require a series of additional measurements for the optimization and control of the configuration: the 14 MeV neutrons, the isotopic composition of the main plasma, the helium ash, and the redistribution and losses of the alpha particles. Moreover a burning plasma environment is in general much more hostile for diagnostics than purely deuterium plasmas. Therefore, in addition to the development and refinement of new measuring techniques, technological advances are also indispensable for the proper characterization of the next generation of devices. On JET an integrated program of diagnostic developments, for JET future and in preparation for ITER, has been pursued and many new results are now available. In the field of neutron detection, the neutron spectra are now routinely measured in the energy range of 1-18 MeV by a time of flight spectrometer and they have allowed studying the effects of rf heating on the fast ions.A new analysis method for the interpretation of the neutron cameras measurements has been refined and applied to the data of the last trace tritium campaign (TTE). With regard to technological upgrades, chemical vapor deposition diamond detectors have been qualified both as neutron counters and as neutron spectrometers, with a potential energy resolution of about one percent. The in situ calibration of the neutron diagnostics, in preparation for the operation with the ITER-like wall, is also promoting important technological developments. With regard to the fast particles, for the first time the temperature of the fast particle tails has been obtained with a new high purity Germanium detector measuring the gamma emission spectrum from the plasma. The effects of toroidal Alfven eigenmodes modes and various MHD instabilities on the confinement of the fast particles have been determined with a combination of gamma ray cameras, neutral particle analyzers, scintillator probe, and Faraday cups. From a more technological perspective, various neutron filters have been tested to allow measurement of the gamma ray emission also at high level of neutron yield.

• OSTI ID: 22058722
• Journal Information: Review of Scientific Instruments, Vol. 81, Issue 10; Other Information: (c) 2010 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALPHA PARTICLES
CALIBRATION
DEUTERIUM
EMISSION SPECTRA
ENERGY RESOLUTION
FARADAY CUPS
GAMMA CAMERAS
GAMMA RADIATION
GE SEMICONDUCTOR DETECTORS
ITER TOKAMAK
JET TOKAMAK
MEV RANGE 10-100
NEUTRON CAMERAS
NEUTRON SPECTRA
NEUTRON SPECTROMETERS
NEUTRONS
OPTIMIZATION
PLASMA DIAGNOSTICS
TIME-OF-FLIGHT SPECTROMETERS
TRITIUM