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Title: Gamma ray imager on the DIII-D tokamak

A gamma ray camera is built for the DIII-D tokamak [J. Luxon, Nucl. Fusion 42, 614 (2002)] that provides spatial localization and energy resolution of gamma flux by combining a lead pinhole camera with custom-built detectors and optimized viewing geometry. This diagnostic system is installed on the outer midplane of the tokamak such that its 123 collimated sightlines extend across the tokamak radius while also covering most of the vertical extent of the plasma volume. A set of 30 bismuth germanate detectors can be secured in any of the available sightlines, allowing for customizable coverage in experiments with runaway electrons in the energy range of 1- 60 MeV. Commissioning of the gamma ray imager includes the quantification of electromagnetic noise sources in the tokamak machine hall and a measurement of the energy spectrum of background gamma radiation. In conclusion, first measurements of gamma rays coming from the plasma provide a suitable testbed for implementing pulse height analysis that provides the energy of detected gamma photons.
ORCiD logo [1] ;  [2] ;  [1] ;  [1] ;  [3] ;  [4] ;  [1] ;  [1]
  1. General Atomics, San Diego, CA (United States)
  2. Oak Ridge Associated Univ., Oak Ridge, TN (United States)
  3. Univ. of California, San Diego, CA (United States)
  4. State Univ. of New York (SUNY), Buffalo, NY (United States)
Publication Date:
Grant/Contract Number:
FC02-04ER54698; AC05-06OR23100; FG02-07ER54912
Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 87; Journal Issue: 4; Related Information: D.C. Pace, C.M. Cooper, D. Taussig, N.W. Eidietis, E.M. Hollmann, V. Riso, M.A. Van Zeeland, M. Watkins, "Gamma Ray Imager on the DIII-D Tokamak", Rev. Sci. Instr. 87, 043507 (2016); Journal ID: ISSN 0034-6748
American Institute of Physics (AIP)
Research Org:
General Atomics, San Diego, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24); USDOE Office of Science (SC), Workforce Development for Teachers and Scientists (WDTS) (SC-27)
Country of Publication:
United States
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1247218