Simulation of low-energy antiproton interactions in a sampling calorimeter

This paper describes the Monte Carlo program used for the simulation of antiproton interactions at intermediate energy inside a brass streamer-tube tracking calorimeter, to be used in a search for antimatter in cosmic rays, in the high atmosphere. The calorimeter is sensitive in the kinetic-energy range 100 - 5000 MeV and the Monte Carlo is tuned in this energy interval both for proton and antiproton interactions. The detector geometry, which consists of a set of plane slabs, may be easily extended to other calorimeter structures.