Source probability in MCNP (Monte Carlo N-Particle) refers to the likelihood that a source particle will be generated from a particular source distribution. It is a critical parameter in simulations that helps define how particles are sampled from the source during the run.
In an MCNP input file, source probability is defined using the SDEF (source definition) card. Parameters such as the probability distribution for energy, position, and direction must be specified to accurately model the source characteristics.
Yes, you can use multiple source probabilities in a single MCNP simulation. This is typically done using the SI (source input) and SP (source probability) cards to define different source distributions and their respective probabilities.
Source probability directly impacts the accuracy of MCNP simulations by influencing how well the source characteristics are represented. Accurate source probabilities ensure that the simulated particle flux and energy distributions closely match the real-world scenario being modeled.
Common errors related to source probability in MCNP include incorrect specification of the source distribution parameters, misalignment of source probability with the physical setup, and improper normalization of probability distributions. These errors can lead to inaccurate simulation results and must be carefully checked.