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Full-spectrum modeling of mobile gamma-ray spectrometry systems in scattering media

David Breitenmoser1,2,*, Alberto Stabilini1, Malgorzata Magdalena Kasprzak1, and Sabine Mayer1

  • 1Department of Radiation Safety and Security, Paul Scherrer Institute (PSI), Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
  • 2Department of Nuclear Engineering & Radiological Sciences, University of Michigan, 2355 Bonisteel Blvd., Ann Arbor, Michigan 48109-2104, USA

  • *Contact author: david.breitenmoser@psi.ch
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Phys. Rev. Applied 25, 014044 – Published 20 January, 2026

DOI: https://doi.org/10.1103/yhz2-xmby

Abstract

Mobile gamma-ray spectrometry (MGRS) systems are essential for localizing, identifying, and quantifying gamma-ray sources in complex environments. Full-spectrum template matching offers the highest accuracy and sensitivity for these tasks but is limited by the computational cost of generating the required spectral templates. Here, we present a generalized full-spectrum modeling framework for MGRS systems in scattering media, enabling near-real-time template generation through dynamic, anisotropic instrument response functions. Benchmarked against high-fidelity brute-force Monte Carlo simulations, our method yields a computational speedup by a factor of O(107), while achieving comparable accuracy with median spectral deviations below 6%. The methodology presented is platform-agnostic and applicable across marine, terrestrial, and airborne domains, unlocking new capabilities for MGRS in a variety of applications, such as environmental monitoring, geophysical exploration, nuclear safeguards, and radiological emergency response.

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Phys. Rev. Applied 25, 014044– Published 20 January, 2026
  • Received 21 June 2025
  • Accepted 26 November 2025
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