Radiation Physics and Engineering
A peer-reviewed journal published by K. N. Toosi University of Technology

Studying the effect of backgrounds on the determination of radiative thermal neutron capture cross-section in the Neutron Powder Diffraction facility of the Tehran Research Reactor

Document Type : Research Article

Authors

Mahya Pazoki 1
Hamid Jafari 1
Zohreh Gholamzadeh 2

1 Department of Radiation Application, Shahid Beheshti University, Tehran, Iran

2 Reactor and Nuclear Safety, Nuclear Science and Technology Research Institute, Atomic Energy Organization of Iran, Tehran, Iran

https://doi.org/10.22034/rpe.2022.349750.1094
Abstract
Neutron data and cross-sections are highly regarded and are essential for developing nuclear equipment such as advanced fission and fusion reactors, accelerators, neutron shielding, physics studies, etc. The neutron cross-section should preferably be measured using a single-energy neutron beam, although the presence of a background in research reactors can affect its accurate determination. The Neutron Powder Diffraction (NPD) facility of Tehran Research Reactor (TRR) has been taken into consideration for measuring the neutron cross-section based on its properties, including neutron monochromator and multiple collimators. In this work, radiative capture cross-sections of Au, In, and Rh materials have been calculated using TRR monochromatic beam. MCNPX is a Monte Carlo particle transport code that has been applied to simulate the measurement system of the neutron cross-section and calculate the reaction rates. The effect of the presence and absence of different sections of the background on the cross-section values was investigated and the results were compared with EXFOR data library for validation. According to the findings, neutron backgrounds can have varying impacts depending on factors such as sample material, the isotope resonance regions, neutron source spatial distribution, and neutron monochromatic energy. However, the presence of fast neutron background contributes to the most uncertainty in the cross section values while its removal produces an average discrepancy from experimental libraries of 7.16%. Also, removing the cold neutron background also causes a relative difference equal to 7.65%.

Highlights

  • Flux distribution and its effect on the numerical value of the cross-section has been investigated.
  • Neutron Powder Diffraction facility of Tehran Research Reactor were considered as a neutron source.
  • Background effects on the calculated cross-sections were compared to the results of the EXFOR data library.
  • Foils of gold, indium, and rhodium have been used as the samples irradiated by monochromatic neutron beam.

Keywords

Cross-section
Neutron activation
TRR
MCNPX
Monochromatic beam
Adib, M. (2005). Cross-section of single-crystal materials used as thermal neutron filters.
Adib, M., Habib, N., Bashter, I., et al. (2011). Mgo single crystal as an efficient thermal neutron filter. Annals of Nuclear Energy, 38(12):2673–2679.
Adib, M., Habib, N., Kilany, M., et al. (2004). Neutron trans- mission through crystalline Fe.
Adib, M. and Kilany, M. (2003). On the use of bismuth as a neutron filter. Radiation Physics and Chemistry, 66(2):81–88.
Adib, M., Naguib, K., Ashry, A., et al. (2002). On the use of lead as a neutron filter. Annals of Nuclear Energy, 29(9):1119–1130.
Brugger, R. M. (1976). A single crystal silicon thermal neutron filter. Nuclear Instruments and Methods, 135(2):289–291.
Celenk, I., Demirel, H., andÖzmen, A. (1991). Measurement of macroscopic and microscopic thermal neutron cross sections of V, Co, Cu, In, Dy and Au using neutron self-absorption properties. Journal of Radioanalytical and Nuclear Chemistry, 148(2):393–401.
Cierjacks, S., Shibata, K., and Issy-les Moulineaux, F. (1994). Blind Intercomparison of Nuclear Models for Predicting Charged Particle Emission, NEA/NSC-DOC93-4. Nuclear Energy Agency, OECD.
Dastjerdi, M. C., Khalafi, H., Kasesaz, Y., et al. (2016). Design, construction and characterization of a new neutron beam for neutron radiography at the Tehran Research Reactor. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 818:1–8.
Drozdowicz, K. (1989). Energy-dependent scattering cross section of plexiglass for thermal neutrons. Technical report, Chalmers Univ. of Tech.
El Abd, A., Taha, G., and Ellithi, A. (2017). A method for measuring macroscopic cross-sections for thermal neutrons. Applied Radiation and Isotopes, 128:318–327.
ENDF (2021). ENDF: Evaluated Nuclear Data File, https://www-nds.iaea.org/exfor/endf.htm#1. Technical report.
Gholamzadeh, Z., Bavarnegin, E., Rachti, M. L., et al. (2018). Modeling of neutron diffractometry facility of Tehran Research Reactor using Vitess 3.3 a and MCNPX codes. Nuclear Engineering and Technology, 50(1):151–158.
Han¸ cerlio˘gullari, A., KORKUT, T., and MADEE, Y. G. A. (2017). The Neutron Macroscopic Cross Sections Calculation of Some Minerals by Using FLUKA Monte Carlo Method. The Online Journal of Science and Technology-July, 7(3).
Harvey, J., MOOK, H., HILL, N., et al. (1988). Nuclear data for science and technology.
Huang, X., Lu, H., Zhao, W., et al. (1998). Neutron activation cross section measurements and evaluations in CIAE. Technical report, International Atomic Energy Agency.
Jacobson, L. A. (1988). Macroscopic thermal neutron capture cross section measurements. IEEE Transactions on Nuclear Science, 35(1):817–821.
Kobayashi, H., Wakao, H., Ikeda, Y., et al. (1992). Macroscopic cross section measurements and defect detection in materials using neutron radiography technique. Journal of Nuclear Science and Technology, 29(11):1045–1053.
Lamarsh, J. R., Baratta, A. J., et al. (2001). Introduction to nuclear engineering, volume 3. Prentice hall Upper Saddle River, NJ.
Pelowitz, D. B. et al. (2005). MCNPXTM user’s manual. Los Alamos National Laboratory, Los Alamos, 5:369.
Pelowitz, D. B. et al. (2011). MCNPXTM user’s manual. Los Alamos National Laboratory, Los Alamos, 5:369.
Rubbia, C., Roche, C., Rubio, J. A., et al. (1995). Conceptual design of a fast neutron operated high power energy amplifier. Technical report.
Steele, E. L. and Meinke, W. W. (1962). Determination of rhodium by thermal neutron activation analysis using g-ray spectrometry. Analytica Chimica Acta, 26:269–274.
Radiation Physics and Engineering
Volume 4, Issue 2
Winter 2023
Pages 9-17

  • Receive Date 30 June 2022
  • Revise Date 05 August 2022
  • Accept Date 18 August 2022

Home

Submit Manuscript

Reviewers

Contact Us