An International Double-blind, Peer - Review Journal by NSTRI

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

1‌. R. J. Woods, A. K. Pikaev, Applied radiation chemistry: radiation processing, John Wiley & Sons, (1993)

2. K. Schwochau, Technetium: chemistry and radiopharmaceutical applications, 2nd Edition John Wiley & Sons, New York, (2008)

3.  F. M. Khan, J. P. Gibbons, The physics of radiation therapy, 5th Edition, Lippincott Williams & Wilkins, United State, (2014)

4‌. ‌ G. ‌Jacobs,  Radiation sterilization of pharmaceuticals: A review, Radiat. Phys. Chem. 26, 133 (1985)

5‌. G. Shani, Radiation dosimetry instrumentation and methods, 2nd Edition, CRC press, United State, (2000)

6‌. International Commission on Radiation Units and Measurements. (1977), Neutron dosimetry for biology and medicine, Report No. 26, United State.

7. G. F. Knoll, Radiation detection and measurement, 4th Edition, John Wiley & Sons, New York, (2010)

8. A. Rimpler, Dose equivalent response of neutron survey meters for several neutron fields, Radiat. Prot. Dosim. 44, 189 (1992).

‌9. J. Chartier et al. Progress on calibration procedures with realistic neutron spectra, Radiat. Prot. Dosim. 57, 61 (1995).

10. R. Tanner et al.  Effect of the energy dependence of response of neutron personal dosemeters routinely used in the UK on the accuracy of dose estimation, National Radiological Protection Board Didcot, UK, (2002).

11. M. Pyshkina, M. Zhukovsky and A. Ekidin, in: Radiation Protection Dosimetry Conference, RAD Conference Proceedings 3, North Macedonia, June (2018) 36-41.

12. G. Raisali et al. Analysis of neutron and gamma-ray streaming along the maze of NRCAM thallium production target room, Appl. Radiat. Isotopes. 64, 940 (2006).

13. H. Ing and S. Makra, Compendium on neutron spectra in criticality accident dosimetry International Atomic Energy Agency, Austria, (1978).

14. R. Griffith, J. Palfalvi and U. Madhvanath, Compendium of neutron spectra and detector responses for radiation protection purposes International Atomic Energy Agency, Austria, (1990).

15. F. Torkzadeh and M. Taheri, Improvement and calibration of a SSNT personal dosemeter and study of importance of albedo factor for dose calculation, Radiat. Prot. Dosim. 125, 224 (2006).

16. A. C. Tássio, et al., Difference in TLD 600 and TLD 700 glow curves derived from district mixed gamma/neutron field irradiations,International Nuclear Atlantic Conference -INAC (2013).

17. International Atomic Energy Agency, International basic safety standards. (2014). Safety standard, Radiation protection and safety of radiation sources, Report No. GSR part 3, Austria.

18. International  Atomic Energy Agency. (2018). Safety standard, Occupational radiation protection, Report No. GSG-7m, Austria.

19.International Commission on Radiation Units and Measurements. (1986). The quality factor in radiation protection, Report NO. 40, United State,