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Measurement of a cold neutron cross section for the 40Ca(n, α)37Ar reaction
Khiloni A Shah1, Sarah T Castro1, Kohlton D Mathis1
1The University of Texas at Austin, Walker Department of Mechanical Engineering, 10100 Burnet Road, Building 159, Austin, TX 78758, United States.
Abstract:
The production of 37Ar gas through the neutron activation of 40Ca is important for underground nuclear explosion monitoring. Some of the activation occurs with thermal neutrons, but the thermal neutron cross section for the 40Ca(n, α)37Ar reaction is not well understood. There are disagreements between the Evaluated Nuclear Data File and the Japanese Evaluated Nuclear Data Library on the existence of the thermal cross section. An experiment was designed at The University of Texas to use alpha spectroscopy to measure the cold neutron cross section. The experiment was repeated five times and a weighted average cross section of 196.7 ± 47.2 mbarns was calculated.
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