Modelling cosmic rays and gamma rays in the Galaxy

An extensive program for the calculation of galactic cosmic-ray propagation has been developed. This is a continuation of the work described in [1]. The main motivation for developing this code [2] is the prediction of diffuse Galactic gamma rays for comparison with data from the cgro instruments egret, comptel, and osse. The basic spatial propagation mechanisms are (momentumdependent) diffusion, convection, while in momentum space energy loss and diffusive reacceleration are treated. Primary and secondary nucleons, primary and secondary electrons, and secondary positrons are included. Fragmentation and energy losses are computed using realistic distributions for the interstellar gas and radiation fields.