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arXiv · 2005.02499

Neutron production in (alpha, n) reactions

V. A. Kudryavtsev·P. Zakhary·B. Easeman
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Abstract

Neutrons can induce background events in underground experiments looking for rare processes. Neutrons in a MeV range are produced in radioactive decays via spontaneous fission and (alpha, n) reactions, and by cosmic rays. Neutron fluxes from radioactivity dominate at large depths (>1 km w. e.). A number of computer codes are available to calculate cross-sections of (alpha, n) reactions, excitation functions and neutron yields. We have used EMPIRE2.19/3.2.3 and TALYS1.9 to calculate neutron production cross-sections and branching ratios for transitions to the ground and excited states, and modified SOURCES4A to evaluate neutron yields and spectra in different materials relevant to high-sensitivity underground experiments. We report here a comparison of different models and codes with experimental data, to estimate the accuracy of these calculations.

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V. A. Kudryavtsev, P. Zakhary, B. Easeman. 2020-05-03. Neutron production in (alpha, n) reactions. https://doi.org/10.1016/j.nima.2020.164095

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