https://doi.org/10.1051/epjconf/202532905006
Measuring and Simulating Neutron Capture γ-Ray Spectra using the RPI γ-Ray Multiplicity Detector
1 Gaerttner LINAC Center, Rensselaer Polytechnic Institute, Troy, NY 12180
2 Naval Nuclear Laboratory, P.O. Box 1072, Schenectady, NY 12301
* e-mail: cookk4@rpi.edu
Published online: 25 June 2025
Accurate modeling of neutron induced capture γ-ray production is essential for many applications such as reactor and shielding calculations, understanding γ-ray heating in critical systems, and non-proliferation efforts. To determine the accuracy of nuclear data evaluations and simulation tools used to transport capture γ-cascades, the 16-segment γ-ray multiplicity NaI(T1) detector at the Rensselaer Polytechnic Institute Gaerttner Linear Accelerator Center has been upgraded to measure neutron capture γ-ray spectra and multiplicity as a function of energy. Several samples including Fe, Mn, Co, Ta, and 235,238U have been measured using the time-of-flight method for incident neutrons in the low-energy region from 0.01 – 100 eV. A new method has been developed to model the event-by-event capture γ-ray cascade energy deposition in the detector array using DICEBOX and a modified version of MCNP-6.2. The method has been validated using 22Na and 60Co coincidence sources and the well-studied thermal 56Fe(n,γ) γ-ray intensities. Additional measured samples will be used for further validation and analysis. The new modeling capabilities coupled with measured γ-ray spectra can be used to test transport codes and nuclear data evaluations of neutron capture γ-rays used to simulate experimental results.
© The Authors, published by EDP Sciences, 2025
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
