I.B. Smirnov PNPI, Russia
The program HEED (W5060) simulates the initial ionization produced by fast charged particles in gases. It is designed for the simulation of drift and proportional chambers. It is based on the PAI model and simulates also a series of secondary processes. The program simulates the primary interactions of the incident fast charged particle with electrons of the material, and the energy dissipation that results in the creation of conduction electrons. Energy dissipation can take place through deceleration of delta-electrons, through absorption of fluorescence photons and so on.
However, the program does not simulate the drift of conduction electrons to cathodes. The program can be run as a stand-alone batch program, and it is connected to Garfield, a drift-chamber simulation program.
The program is written in Fortran-77.