WA 80 BGO calorimetry electronics

The authors describe instrumentation designed for bismuth germinate (BGO) scintillator-based calorimetry of particles covering a very wide range of energies. In the case of the WA 80 experiment, it was desired to cover the range from <50 MeV to >50 GeV with energy resolution limited by the BGO scintillator. It was decided that a goal of the electronics design should be 0.1% resolution over that energy range. The preamplifier and pulse processor developed specifically for the WA 80 experiment are described. The preamplifier was designed for high detector capacitance, low integral and differential nonlinearity and low power consumption. The pulse processor is a time-variant shaping amplifier with integral peak-detect-and-hold and automatic gain selection circuits. The preamplifier and pulse processor combination has more than 20 b of effective resolution when used with an external 12-b analog-to-digital converter (ADC). An array of BGO instrumented with 100 preamplifiers and pulse processors was used in beam tests at CERN. Preliminary results from those tests are presented