A 4π light-charged particle Si detector as a trigger device for in-beam γ-ray spectroscopy

A 4π Si-ball detector system has been constructed as a trigger device for the γ-ray spectrometer GASP. The construction and operation of the detector is reported, together with a brief description of the electronics and of the data acquisition system used. Results are presented for the 32S + 40Ca reaction at 140 MeV of32S beam energy.