Summing adjacent signals from BGO array in neutron stimulated emission computed tomography

Neutron stimulated emission computed tomography (NSECT) is a new approach for biological spectroscopy and imaging. Since the gamma-ray photons emitted from stimulated element have energies from 100 keV to about 6 MeV, previous reports have proposed that the projection path can be defined by the neutron beam. In this paper, a good energy resolution method has been applied, whose performance is analysed through simulations. Using signals from a single BGO crystal, it is impossible to achieve good energy resolution for such high-energy photons. But when summing additional signals from adjacent crystals, the energy spectrum becomes much better. Using an energy window with energy resolution of 90 keV, an average intrinsic spatial resolution of 3.938 mm FWHM is obtained.