Abstract
Detecting illicit material moving through RPMs is in the interest of national security. Eliminating background counts increases the possibility of detecting a source passing through the RPM as determined by an increased SNR. The numerical approximation of the analytical solution provided expected values for the MCNP model and demonstrated that geometry and tallies were configured correctly. The MCNP model allowed numerous parameters to be changed easily to maximize the SNR. The ideal rectangular mesh configuration resulted in a 109% increase in SNR when the source was present somewhere centered on the detectors. When the source was outside of the RPM, then the SNR decreased significantly, but because the RPM alarm system would be triggered by only one inflated count output, the RPM would have a much higher SNR when the collimator is used. The ability to enhance the sensitivity to point-like sources (vs. distributed sources) can be a useful RPM feature. This increased SNR indicates that when implemented, metal lattice collimators can enhance the performance of existing deployed RPMs with no other modifications necessary.
| Original language | English |
|---|---|
| Pages (from-to) | 848-851 |
| Number of pages | 4 |
| Journal | Transactions of the American Nuclear Society |
| Volume | 131 |
| Issue number | 1 |
| DOIs | |
| State | Published - 2024 |
| Event | 2024 Transactions of the American Nuclear Society on Winter Conference and Expo, ANS 2024 - Orlando, United States Duration: Nov 17 2024 → Nov 21 2024 |
Funding
This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). This research was sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the US Department of Energy.