Speakers
Description
Cross-sections for neutron-induced interactions with molybdenum, in particular for the neutron capture reaction, play an important role in various fields ranging from nuclear astrophysics to safety assessment of conventional nuclear power plants and the development of innovative technologies. It is found as a pollutant in pre-solar silicon carbide grains and it has a crucial role in stellar nucleosynthesis in Asymptotic Giant Branch (AGB) stars[1]. During reactor operation molybdenum is produced as a fission product. Moreover, the use of molybdenum for the production of Accident Tolerant Fuel (ATF) is under study [2]. It is a promising candidate for new generation research reactors using UMo alloys with Low Enriched Uranium (LEU)[3]. This shows the importance of an accurate knowledge of the total and capture cross-section for molybdenum isotopes.
Experimental data in the literature for the capture cross-section of Mo isotopes suffer from large uncertainties. This is also reflected in the large uncertainties of the cross-sections recommended in the ENDF/B-VIII.0 library[4]. Below 1 eV the relative uncertainty of the capture cross-section is above 18% for $^{94}$Mo and around 40% for $^{96}$Mo, while above 2 keV the uncertainties are in the order of 10-20% for $^{94,95,96}$Mo. One of the reasons for these large uncertainties is related to the absence of transmission data for enriched samples.
In this contribution results of accurate transmission and capture cross-section measurements using natural Mo samples and samples enriched in $^{94}$Mo, $^{95}$Mo and $^{96}$Mo are presented. The data cover an energy region from thermal energy (0.025 eV) up to hundreds of keV. The capture measurements are performed at the n_TOF facility at CERN (CH) and the GELINA facility at JRC-Geel (BE). The transmission measurements are performed at GELINA. The experimental data, i.e. transmissions and capture yields, will be delivered to the EXFOR data library and will be used to improve the evaluated cross-section data for neutron interactions with $^{94,95,96}$Mo in the resolved and unresolved resonance region.
REFERENCES
[1] N.Liu, T.Stephan, S.Cristallo et al., Astrophysical Journal, 881, 28 (2019).
[2] B. Cheng, Y.-J. Kim, P. Chou, Nuclear engineering and Technology, 48, 16-25 (2016).
[3] P. Herve et al., EPJ Nuclear Sciences & Technologies, 4, 49 (2018).
[4] D.A. Brownet et al., Nuclear Data Sheets, 148, 1 (2018).
