Recent MCNP developments

The authors report both the status and developments in the Monte Carlo neutron-photon (MCNP) radiation transport computer code and two items of more general interest to computational physics: the accuracy of modern physics computer codes and the performance of scientific workstations. Benchmark studies indicate not only that MCNP is accurate but also that modern computer codes can give answers basically as accurate as the physics data that go into them. Even deep penetration problems can correct to within a factor of two after 10 to 25 mean free paths of penetration. Monte Carlo calculations, once thought to be too expensive to run routinely, can now be run effectively on desktop computers which compete with the supercomputers of yesteryear.<<ETX>>