Measurement of spectral averaged cross sections of capture reactions in the LR-0 reference neutron field

• Published in: Applied radiation and isotopes Vol. 210; p. 111351
• Main Authors: Losa, Evžen, Košťál, Michal, Šimon, Jan, Czakoj, Tomáš
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.08.2024
• Subjects: Capture reactions; Cross-section validation; LR-0 reactor; Weighted cross-section; Cross-section validation; LR-0 reactor; Capture reactions; Weighted cross-section
• ISSN: 0969-8043; 1872-9800
• DOI: 10.1016/j.apradiso.2024.111351

Nuclear data evaluations are periodically updated to render state of the art of knowledge, and the independent validation experiments are still of interest of the community. Current work describes validation of selected capture reactions used for monitoring of thermal neutrons in mixed fields, as well as reactions responsible for activation of components exposed to neutron flux. The validation was performed also for reaction 50Cr (n,γ), which is very important reaction directly affecting criticality safety, because chromium is essential component of stainless steel used as structural component of the core baffle closely adjoining to nuclear fuel. Described experiments were performed in reference neutron field of the LR-0 reactor. The activation rate was derived by gamma spectrometry using well-characterized HPGe detector. It was found that the capture cross sections for the dosimetry reactions 23Na (n,γ), 58Fe (n,γ), and 59Co (n,γ) agreed well within 10 % with calculations in thermal and epithermal region, but larger discrepancy was found for the isotopes of tin. •Experimental validation of capture cross sections was performed in the reference neutron field of the LR-0 reactor.•Homogeneity of the neutron field in the irradiation position has been proven by calculation and experiment.•Main dosimetry reactions as 23Na (n,γ), 58Fe (n,γ), and 59Co (n,γ) agree well with calculation predictions using different nuclear data libraries, except of the capture reactions on isotopes of tin.