Radiation Transport Simulation Codes 

Transport of radiation through matter can be calculated by Monte Carlo simulation codes. The most popular among them are GEANT (maintained by CERN, Switzerland) and MCNP (maintained by LANL, United States) that use ENDF reaction cross-section library as input.

GEANT is a toolkit for the simulation of the passage of particles through matter. Its application areas include high-energy physics and nuclear experiments, medical, accelerator and space physics studies.

MCNP is a general-purpose Monte Carlo N-Particle code for neutron, photon, electron, or coupled neutron/photon/electron transport. Areas of application include, but are not limited to radiation protection and dosimetry, radiation shielding, homeland security, radiography, medical physics, nuclear criticality safety, detector design and analysis, nuclear oil well logging, accelerator target design, fission and fusion reactor design, decontamination and decommissioning. MCNP(X) is a version of the code for charged particles.