Performance of a new signal processing system for a detector array

To measure neutron cross-section data of minor actinides, we construct a 4-pi Ge-spectrometer utilizing multiple gamma-ray detection method. This spectrometer consists of 30 Ge crystals (40 detector outputs) and 128 BGO anti-Compton shields. Generally, a data acquisition system for such a big Ge spectrometer consists of many NIM modules; it requires large space and huge cost. To overcome these problems, we developed a new data acquisition system with digital signal processing techniques. This system is mounted in a 19 inches VME sub-rack, and the cost of this system is greatly reduced. Obtained FWHMs (2.5 similar to 2.8 keV at 1.33 MeV) show good performances as normal MCA even with short shaping time and much higher channel density. The dead time of this system is only 3.2 micro sec per event. Thus good energy resolution is achieved with short shaping time and short dead time.