Present and future capabilities of MCNP

Several new capabilities have been added to MCNP4C including: (1) macrobody surfaces; (2) the superimposed mesh importance functions, so that it is no longer necessary to subdivide geometries for variance reduction; and (3) X lib graphics and DVF Fortran 90 for PCs. There are also improvements in neu tron physics, electron physics, perturbations, and parallelization. In the more distant future we are working on adaptive Monte Carlo code modernizati on, more parallelization, visualization, and charged particles. Published b y Elsevier Science Ltd.