A new Excel-based Monte Carlo transport code for simulating energy response spectra and efficiencies in gamma-ray detection materials

• Published in: Radiation physics and chemistry (Oxford, England : 1993) England : 1993), 2024-05, Vol.218, p.111616, Article 111616
• Main Authors: Hila, Frederick C., Guillermo, Neil Raymund D., Amorsolo, Alberto V., Mercado, Candy C.
• Format: Article
• Language: English
• Subjects: Full-energy peak efficiency; Gamma spectrometry; Microsoft Excel; Monte Carlo simulations; PHITS; Radiation detectors
• ISSN: 0969-806X
• DOI: 10.1016/j.radphyschem.2024.111616

This study presents and assesses a new, user-friendly, and Excel-based Monte Carlo photon transport code, specifically designed to simulate Gaussian energy broadened response spectra of gamma-ray detector materials. This vectorized code utilizes the EPICS2017 photoatomic data library, with unionized energy grid construction, to facilitate precise and efficient photon transport simulations in any user-defined materials composition. Performance benchmarks were conducted using PHITS 3.31, with both basic and detailed models of a gamma-ray scintillator system, and detection crystals of NaI(Tl) and LaBr3(Ce). These benchmarks spanned a wide array of photon source monoenergetic emissions. Detector model efficiency was determined through automated peak area analysis, employing algorithms from the Ortec GammaVision software. The results indicated only minor spectral differences between the Excel-based code and the PHITS models, particularly within the range of practical gamma-ray energies and near-zero source-detector distances. Efficiency curves demonstrated good agreement between the Excel-based code and PHITS models, especially within the energy range of approximately 200 keV to a few MeV, with increasing agreement as detector crystal size increased. Comparisons were conducted with the existing data in literature at source-detector distances of 2 cm and 5 cm, using a detector crystal size of 2”. These comparisons support the code’s validity and its implementation of a basic geometry. This new Excel-based code appears as a promising tool with potential applications in radiation detector characterization and materials research. •Excel-based Monte Carlo code for broadened gamma-ray response spectrum.•Utilizes EPICS2017 data with unionized energy grid.•Benchmarked with PHITS basic and detailed detector models.•Performed automated peak analysis of multiple spectra for efficiency curves.•Built code agreed with literature efficiency values.