Measurement of thick-target gamma-ray production yields of the 7Li(p, p′)7Li and 7Li(p, γ)8Be reactions in the near-threshold energy region for the 7Li(p, n)7Be reaction

Authors:   Tatsuhiro Saito,Tatsuya Katabuchi,Brian Hales,Masayuki Igashira
Journal: Journal of Nuclear Science and Technology
https://doi.org/10.1080/00223131.2016.1255576
Abstract: The gamma-ray production reactions, 7Li(p, p′)7Li and 7Li(p, γ)8Be, occur along with the neutron production reaction 7Li(p, n)7Be in a p-Li neutron source. These gamma-ray production reactions contribute to a patient’s absorbed dose in boron neutron capture therapy (BNCT) when using a neutron beam from the 7Li(p, n)7Be reaction. The present work experimentally determined the thick-target gamma-ray production yields of the 7Li(p, p′)7Li and 7Li(p, γ)8Be reactions at incident proton energies of 1.670 and 1.870 MeV. The present results were compared with previous measurements. The gamma-ray production yield of 7Li(p, p′)7Li was measured to be 30%–50% smaller than as reported by previous studies. For the 7Li(p, γ)8Be reaction, the present thick-target yield is 30% smaller than one estimated from cross-section data measured in previous studies. The results must be included in future dose evaluation for BNCT using a p–Li neutron source.