Large solid angle detector for hard photons and neutral pions from nucleus-nucleus collisions below 100 MeV/u
A lead glass spectrometer has been developed for the detection of high energy gamma-rays and π0s produced below the N-N threshold in heavy-ion collisions at intermediate energies. The design of the detector is presented and its properties (i.e. efficiency, linearity and resolution) are investigated for various working modes. For photons, it accesses a big portion of the angular distribution with a dynamic range from 20 to 250 MeV and a solid angle of 21.6%. For π0, it covers the whole angular range and allows the detection of π0 up to a kinetic energy of about 400 MeV with a mean efficiency around 1%. Despite its moderate energy resolution this high efficiency instrument is particularly adapted to the low production rates occurring in medium energy range heavy-ion collisions.