Effect of the calibration in water and the build-up cap on the Mg(Ar) ionization chamber measurements.

نویسندگان

  • H Koivunoro
  • H Hyvönen
  • J Uusi-Simola
  • I Jokelainen
  • A Kosunen
  • M Kortesniemi
  • T Seppälä
  • I Auterinen
  • S Savolainen
چکیده

Magnesium-walled argon gas flow ionization chamber (Mg(Ar)) is used for photon dose measurements in the epithermal neutron beam of FiR 1 reactor in Finland. In this study, the photon dose measurements were re-evaluated against calculations applying a new chamber calibration factor defined in water instead of in air. Also, effect of the build-up cap on the measurements was investigated. The new calibration factor provides improved agreement between measured and calculated photon dose. Use of the build-up cap does not affect the measured signal in water in neutron beam.

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عنوان ژورنال:
  • Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine

دوره 69 12  شماره 

صفحات  -

تاریخ انتشار 2011