Beamline Improvements to the MInes NEutron Radiography (MINER) Facility

The MInes NEutron Radiography (MINER) facility provides students and researchers at the Colorado School of Mines with the capability to perform neutron imaging at the Geological Survey TRIGA Reactor (GSTR). The current beamline consists of a 1.5 inch innerdiameter aluminum pipe routed from the reactor up to an experiment station in the reactor bay. There are several limitations associated with the current beamline, including a relatively small beam diameter which limits the size of objects which can be successfully imaged, and a tendency toward beamline misalignment, resulting in non-uniform fluxes and high radiation levels in the reactor bay. A second generation beamline, currently under construction as the focus of this project, is intended to overcome these drawbacks and improve the overall performance of the MINER facility. MCNP analysis has been performed throughout this project to aid with beamline design. Part of this analysis has shown that the addition of a pre-collimator (intended to accommodate various beam filters) greatly reduces the fraction of scattered neutrons at the imaging plane, and eliminates the need for a neutron absorbing liner inside the collimator. Use of molecular dynamics to evaluate tributyl phosphate and diamylamyl phosphonate containing systems