MCNPX-PoliMi Post-processing Algorithm for Detector Response Simulations

In the field of nuclear material detection and characterization,Monte Carlo simulations provide valuable insight into complexradiation transport problems. However, in many applications, itis the detector response that is desired. MPPost is a FORTRANprogram that has been developed to interpret the results from theMonte Carlo code MCNPX-PoliMi and return a realistic predictionof the detector response. This program is an enhancedversion of an earlier MCNP-PoliMi post processor written inMatlab.1 The conversion to a FORTRAN based algorithm allowsMPPost to process much greater volumes of data that would beimpossible to handle with a Matlab based equivalent. This paperdescribes the development of MPPost and outlines its capabilities.MPPost was designed specifically for the MCNPX-PoliMi dataoutput file. This file consists of a comprehensive list of collisionevents that occur in each detector cell. The MPPost program usesthis summary of collision events to model the response in a detectorvolume. By characterizing the response of a detector with empiricallydetermined parameters, accurate simulation of the detector responseis obtained. In addition, the program can perform several commonanalysis techniques. These are described in this report.