I used ISAJET to generate 20000 minimum bias events. These I fed to GEANT, using a threshold of 5 MeV for particle transport. To keep from wasting time I cut out non-muons and non-neutrons below 20 MeV when they were more than 10 cm inside a calorimeter. I stored hit information for the IMU drift chambers, the wall counters, the barrel counters, and the toroid counters.
There were two main GEANT models:
The GEANT model includes the IMU system, the beampipe, the central E/M and hadron calorimeters, the Wall calorimeter, and the hadronic plug calorimeter. The silicon is also present but not turned on. It uses the Run I solenoid magnetic field map. I did not include beam line shielding, since I did not expect backscatter to play a major role, nor did I include the CMEX. See Figure 1.