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  • Open Access

Identifying neutron sources using recoil and time-of-flight spectroscopy

David Breitenmoser*, Ricardo Lopez, Shaun D. Clarke, and Sara A. Pozzi

  • Department of Nuclear Engineering and Radiological Sciences, University of Michigan, 2355 Bonisteel Blvd., Ann Arbor, Michigan 48109-2104, USA

  • *Contact author: dbreiten@umich.edu
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Phys. Rev. Applied 25, 064013 – Published 3 June, 2026

DOI: https://doi.org/10.1103/v6j6-f4rx

Abstract

Identification of neutron sources is central to nuclear physics and its applications, from planetary science to nuclear security, yet direct source discrimination from measured neutron spectra remains fundamentally elusive. Here, we introduce a Bayesian protocol that directly infers source ensembles from measured neutron spectra by combining full-spectrum template matching with probabilistic evidence evaluation. Applying this protocol to recoil and time-of-flight spectroscopy, we recover single- and two-source configurations with strong statistical significance (beyond 4σ) at event counts as low as ∼103. These results demonstrate that neutron spectral signatures can be leveraged for robust source identification, opening a new observational window for both fundamental research and operationally driven applications.

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Phys. Rev. Applied 25, 064013– Published 3 June, 2026
  • Received 12 December 2025
  • Revised 16 March 2026
  • Accepted 30 April 2026
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