An International Peer - Reviewed Journal by Nuclear Science & Technology Research Inistitute

Document Type : Research paper

Authors

1 Radiation Applications Research School, Nuclear Science and Technology Research Institute, AEOI, P.O. Box: 11365-3486, Tehran. Iran.

2 Reactor and Nuclear Safety Research School, Nuclear Science and Technology Research Institute, AEOI, Tehran, Iran

3 Radiation Applications Research School, Nuclear Science and Technology Research Institute, AEOI, Tehran, Iran

Abstract

One problem in neutron dosimetry is that dosimeter responses per unit dose-equivalent in measurement and calibration fields are different. Hence, the neutron dose suffers a large uncertainty. In this work, a correction method is introduced to modify the dosimeters response in the fields with known energy spectra. To examine it, responses of thermoluminescence dosimeters (TLDs) to fast neutrons in 241Am-Be (calibration), 252Cf and 239Pu-Be fields for four personal dose-equivalents (Hp (10) values) of 5, 10, 15 and 20 mSv are measured. The results obtained reveal that the maximum differences of the original responses measured in 252Cf and 239Pu-Be fields from 241Am-Be field are 15% and 42%, respectively. After correction, above differences reduce to 4.7% and 10.8%. Finally, it can be concluded that the method proposed here, improves the accuracy of dose measurement in the neutron fields with known energy spectra.

Keywords

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