ITS: the integrated TIGER series of electron/photon transport codes-Version 3.0

Abstract
The ITS system is a powerful and user-friendly software package permitting state-of-the-art Monte Carlo solution of linear time-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Version 3.0 is a major upgrade of the system with important improvements in the physical model, variance reduction, I/O, and user friendliness. Improvements to the cross-section generator include the replacement of Born-approximation bremsstrahlung cross section with the results of numerical phase-shift calculations, the addition of coherent scattering and binding effects in incoherent scattering, an upgrade of collisional and radiative stopping powers, and a complete rewrite to Fortran 77 standards emphasizing Block-IF structure. Improvements in the Monte Carlo codes are also described.