Combined detectors based on ZnSe(Te), CsI(Tl) and Si-PIN-PD for separate detection of alpha, beta and gamma radiation

Combined detectors (CD) comprising ZnSe(Te), CsI(Tl), and Si-PIN-PD can be used for detection of charged particles and gamma quanta. The detection is based on selective sensitivity and the different decay times of these scintillators for these kinds of radiations. In this paper, we outline possibilities and limitations of CD in which signals are read by an 18/spl times/18 mm/sup 2/ Hamamatsu S3204 Si-PIN-PD placed on the back side of CsI(Tl) crystal. A specially designed charge-sensitive preamplifier connected to a PD has equivalent noise level of 700 electrons during shaping time of 5 /spl mu/s. The CD-Si-PIN-PD system is compatible with modern computers.