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| Monte Carlo Simulation of Physical Parameters for Air Kerma Measurement by Graphite Pancake Ionization Chamber |
| WANG Kun1,LI Tao2,JIN Sun-jun1,YANG Xiao-yuan1,FAN Tie-shuan2 |
1. National Institute of Metrology, Beijing 100029, China
2. Institute of Heavy Ion Physics, School of Physics, Peking University, Beijing 100871, China |
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Abstract In order to establish the air kerma primary standard based on a graphite pancake ionization chamber for 60Co gamma rays, the radiation field and related physical parameters of the chamber are calculated by the Monte Carlo simulation method. The γ-ray energy spectra and fluence distributions are calculated by the model built by BEAMnrc code, the parameters of the graphite pancake ionization chamber in 60Co γ-ray radiation filed are calculated by EGSnrc code. The combined standard uncertainty of the parameters of the chamber calculated by Monte Carlo method is 0.20%, the results of simulation are accord with results of the same structural chamber from the ARPANSA in the region of the uncertainty. And the change of the values with the primary standard based on a sphere-cylindrical graphite ionization chamber is under expected.
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Received: 26 November 2014
Published: 29 July 2016
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2016, Vol. 37 
