Development of a Method of Thermal‐Neutron Capture Cross Section Measurement by Unfolding Prompt Gamma‐Ray Spectra

A method of thermal neutron‐capture cross‐section measurement by using a pair spectrometer and unfolding prompt gamma‐ray spectra is described. To evaluate the validity of the method, it was applied for the measurement of the thermal neutron cross section of ¹⁴N. A pair spectrometer system was used to measure prompt gamma rays emitted from ¹⁵N produced by thermal neutron capture. Response functions of the system were calculated by using EGS‐4 code. To verify the reproducibility of the response functions, the measured spectrum of prompt gamma rays of ¹⁵N was reproduced by using EGS‐4 code, which was used for calculating response functions.