Total radiative neutron capture in (n,g) nuclear reactions

 1 March 2021                             Credit: BNC / T. Belgya



The gamma photons interact with the detector materials of the spectrometers in a complex way, resulting in energy-dependent detector response functions. A complete set of detector response functions, i.e. the gamma spectra corresponding to incremental gamma-ray energies up to 12 MeV, were obtained by geant4 simulations and used to unfold the experimental gamma spectra. The unfolding successfully removed the continuous Compton-background and the escape peaks related to a full-energy peak but preserved the shape and area of the full-energy peak itself. We finally demonstrated the applicability of this approach in quantifying the total radiative neutron capture cross-sections of the 14N(n,g) reaction, where an excellent agreement with literature data was found.

Tamás Belgya, László Szentmiklósi: Monte-Carlo calculated detector response functions to unfold radiative neutron capture spectra, Nucl. Instr. Meth A. 991, 2021, 165018


The raw (red) and the unfolded (blue) gamma spectrum of a 60Co gamma-ray source, as measured at the Budapest PGAA spectrometer. Black band indicates the confidence interval of the counts.