title: Effect of the calibration in water and the build-up cap on the Mg(Ar) ionization chamber measurements.
abstract: 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.
authors.affiliation: Boneca Corporation, Helsinki, Finland. hanna.koivunoro@helsinki.fi
authors.forename: H
authors.initials: H
authors.lastname: Koivunoro
authors.forename: H
authors.initials: H
authors.lastname: Hyvönen
authors.forename: J
authors.initials: J
authors.lastname: Uusi-Simola
authors.forename: I
authors.initials: I
authors.lastname: Jokelainen
authors.forename: A
authors.initials: A
authors.lastname: Kosunen
authors.forename: M
authors.initials: M
authors.lastname: Kortesniemi
authors.forename: T
authors.initials: T
authors.lastname: Seppälä
authors.forename: I
authors.initials: I
authors.lastname: Auterinen
authors.forename: S
authors.initials: S
authors.lastname: Savolainen