Cross section measurement for the 14N(n,α0,1)11B reactions in the 4.5–11.5 MeV neutron energy region.

With more accurate measurement method for gas samples, cross sections of the ¹⁴N(n,α_0,1)¹¹B reactions were measured at 24 energy points in the 4.5–11.5 MeV neutron energy region based on the 4.5 MV Van de Graaff accelerator at Peking University and the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE). The average neutron fluence (Φ) through the gas sample was obtained through the combination of a highly enriched ²³⁸U₃O₈ sample and the simulation based on SuperMC. The cross sections of the ¹⁴N(n,α₀)¹¹B reaction measured using the gas sample and the solid samples are in agreement with each other. R-matrix analysis was carried out for the n + ¹⁴N system using code RAC in the neutron energy region below 30 MeV. A possible valley structure in both the excitation functions of the ¹⁴N(n,α_0,1)¹¹B reactions in the 10–11 MeV neutron energy region was found for the first time. [ABSTRACT FROM AUTHOR]