Neutron energy spectrum reconstruction using 2-D track scintillation images of recoil protons

In this paper, a method based on two-dimensional (2-D) tracks of recoil protons were used to reconstruct the neutron spectrum. Recoil-proton track imaging is a technique to optically record the tracks of recoil protons in a gaseous scintillator via real-time imaging devices. Scintillation luminescence images represent the 2-D tracks of recoil protons and can directly reflect the neutron energy spectra. Since the track image is 2-D, more information can be obtained. The satisfactory performance of the recoil proton track imaging was determined via Monte Carlo simulations. A series of recoil proton track images were generated using the Geant4 toolkit as the detector response. The neutron energy spectrum was unfolded via a genetic algorithm. Compared with 1-D recoil proton track images, this method has the advantage of being able to achieve a finer resolution for the energy spectrum. Several different neutron energy test spectra were used in this study and it was found that the method was stable and provides accurate results efficiently.