Definition of the radiation fields for the JET gamma-ray spectrometer diagnostics

Vasile Zoita, Sorin Soare, Teddy Craciunescu, Marian Curuia, Vasily Kiptily, Nick Balshaw, Patrick Blanchard, David Croft, Andrea Murari, Brian Syme

Research output: Contribution to journalArticle

3 Citations (Scopus)


The JET gamma-ray diagnostics system provides information on the behaviour of fast particles within the tokamak plasma. Information on the spatial distribution of the interacting fast particles is obtained from the gamma-ray cameras, while energy distribution information is provided by gamma-ray spectrometers. These techniques have been successfully applied so far in fast particle simulation experiments at JET. The extension of these diagnostics to high performance discharges with high neutron yields is not straightforward due to the background gamma-ray emission induced by neutrons. Two gamma-ray diagnostics upgrade projects at JET addressed this issue by developing neutron/gamma radiation filters ("neutron attenuators") and collimators for a proper definition of the radiation (neutron and gamma) fields along the diagnostics line-of-sight. A pair of neutron/gamma collimators working in a tandem configuration have been designed and constructed for the JET quasi-tangential gamma-ray spectrometer. The tandem collimators were designed to provide shielding factors of about 5 × 102for 2.45 MeV neutrons and about 103for 9 MeV gamma-rays. The devices have been installed on the JET machine and the paper presents the first experimental results. A similar tandem collimator system was designed for deuterium-tritium experiments on JET. The results of neutron-photon transport calculations for 14.1 MeV neutrons are also presented. © 2013 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)1366 - 1370
Number of pages5
JournalFusion Engineering and Design
Issue number6-8
Publication statusPublished - 2013
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Civil and Structural Engineering
  • Materials Science(all)
  • Nuclear Energy and Engineering
  • Mechanical Engineering

Cite this

Zoita, V., Soare, S., Craciunescu, T., Curuia, M., Kiptily, V., Balshaw, N., ... Syme, B. (2013). Definition of the radiation fields for the JET gamma-ray spectrometer diagnostics. Fusion Engineering and Design, 88(6-8), 1366 - 1370.