Measurement of (23)Na(n,2n) cross section in well-defined reactor spectra

Michal Košťál; Marie Švadlenková; Petr Baroň; Ján Milčák; Martin Mareček; Jan Uhlíř

doi:10.1016/j.apradiso.2016.02.003

Measurement of (23)Na(n,2n) cross section in well-defined reactor spectra

Appl Radiat Isot. 2016 May:111:1-7. doi: 10.1016/j.apradiso.2016.02.003. Epub 2016 Feb 6.

Authors

Michal Košťál¹, Marie Švadlenková², Petr Baroň², Ján Milčák², Martin Mareček², Jan Uhlíř²

Affiliations

¹ Research Center Rez Ltd, 250 68 Husinec-Rez 130, Czech Republic. Electronic address: Michal.Kostal@cvrez.cz.
² Research Center Rez Ltd, 250 68 Husinec-Rez 130, Czech Republic.

PMID: 26894323
DOI: 10.1016/j.apradiso.2016.02.003

Abstract

The present paper aims to compare the calculated and experimental reaction rates of (23)Na(n,2n)(22)Na in a well-defined reactor spectra of a special core assembled in the LR-0 reactor. The experimentally determined reaction rate, derived using gamma spectroscopy of irradiated NaF sample, is used for average cross section determination. The resulting value averaged in spectra is 0.91±0.02µb. This cross-section is important as it is included in International Reactor Dosimetry and Fusion File and is also relevant to the correct estimation of long-term activity of Na coolant in Sodium Fast Reactors. The calculations were performed with the MCNP6 code using ENDF/B-VII.0, JEFF-3.1, JEFF-3.2, JENDL-3.3, JENDL-4, ROSFOND-2010 and CENDL-3.1 nuclear data libraries. Generally the best C/E agreement, within 2%, was found using the ROSFOND-2010 data set, whereas the worst, as high as 40%, was found using the ENDF/B-VII.0.

Keywords: (22)Na; Cross section measurement; LR-0; Sample irradiation; Sodium induced activity.