Open Access

Inclusive Search for Anomalous Single-Photon Production in MicroBooNE

P. Abratenko ³⁸, D. Andrade Aldana ¹⁴, L. Arellano ²¹, J. Asaadi ³⁷, A. Ashkenazi ³⁶, S. Balasubramanian¹², B. Baller ¹², A. Barnard ²⁸, G. Barr ²⁸ et al. (MicroBooNE Collaboration^*)

G. Barr ²⁸, D. Barrow ²⁸, J. Barrow ²⁵, V. Basque ¹², J. Bateman ^15,21, O. Benevides Rodrigues ¹⁴, S. Berkman ²⁴, A. Bhat ⁷, M. Bhattacharya ¹², M. Bishai ³, A. Blake ¹⁸, B. Bogart ²³, T. Bolton ¹⁷, M. B. Brunetti ⁴⁰, L. Camilleri ¹⁰, D. Caratelli ⁴, F. Cavanna ¹², G. Cerati ¹², A. Chappell ⁴⁰, Y. Chen ³², J. M. Conrad ²², M. Convery ³², L. Cooper-Troendle ²⁹, J. I. Crespo-Anadón ⁶, R. Cross ⁴⁰, M. Del Tutto ¹², S. R. Dennis ⁵, P. Detje ⁵, R. Diurba ², Z. Djurcic ¹, K. Duffy ²⁸, S. Dytman ²⁹, B. Eberly ³⁴, P. Englezos ³¹, A. Ereditato ^7,12, J. J. Evans ²¹, C. Fang ⁴, W. Foreman ^14,19, B. T. Fleming ⁷, D. Franco ⁷, A. P. Furmanski ²⁵, F. Gao ⁴, D. Garcia-Gamez ¹³, S. Gardiner ¹², G. Ge ¹⁰, S. Gollapinni ¹⁹, E. Gramellini ²¹, P. Green ²⁸, H. Greenlee ¹², L. Gu¹⁸, W. Gu ³, R. Guenette ²¹, P. Guzowski ²¹, L. Hagaman ⁷, M. D. Handley ⁵, O. Hen ²², C. Hilgenberg ²⁵, G. A. Horton-Smith ¹⁷, A. Hussain ¹⁷, B. Irwin²⁵, M. S. Ismail ²⁹, C. James¹², X. Ji ²⁶, J. H. Jo ³, R. A. Johnson ⁸, D. Kalra ¹⁰, G. Karagiorgi ¹⁰, W. Ketchum ¹², M. Kirby ³, T. Kobilarcik ¹², N. Lane ^15,21, J.-Y. Li ¹¹, Y. Li ³, K. Lin ³¹, B. R. Littlejohn ¹⁴, L. Liu ¹², W. C. Louis ¹⁹, X. Luo ⁴, T. Mahmud ¹⁸, C. Mariani ³⁹, D. Marsden²¹, J. Marshall ⁴⁰, N. Martinez¹⁷, D. A. Martinez Caicedo ³³, S. Martynenko ³, A. Mastbaum ³¹, I. Mawby ¹⁸, N. McConkey ³⁰, L. Mellet ²⁴, J. Mendez²⁰, J. Micallef ^22,38, A. Mogan ⁹, T. Mohayai ¹⁶, M. Mooney ⁹, A. F. Moor ⁵, C. D. Moore¹², L. Mora Lepin ²¹, M. M. Moudgalya ²¹, S. Mulleriababu², D. Naples ²⁹, A. Navrer-Agasson ^15,21, N. Nayak ³, M. Nebot-Guinot ¹¹, C. Nguyen ³¹, J. Nowak ¹⁸, N. Oza ¹⁰, O. Palamara ¹², N. Pallat ²⁵, V. Paolone ²⁹, A. Papadopoulou ¹, V. Papavassiliou ²⁷, H. B. Parkinson ¹¹, S. F. Pate ²⁷, N. Patel ¹⁸, Z. Pavlovic ¹², E. Piasetzky ³⁶, K. Pletcher ²⁴, I. Pophale ¹⁸, X. Qian ³, J. L. Raaf ¹², V. Radeka³, A. Rafique ¹, M. Reggiani-Guzzo ¹¹, J. Rodriguez Rondon ³³, M. Rosenberg ³⁸, M. Ross-Lonergan ¹⁹, I. Safa ¹⁰, D. W. Schmitz ⁷, A. Schukraft ¹², W. Seligman ¹⁰, M. H. Shaevitz ¹⁰, R. Sharankova ¹², J. Shi ⁵, E. L. Snider ¹², M. Soderberg³⁵, S. Söldner-Rembold ^15,21, J. Spitz ²³, M. Stancari ¹², J. St. John¹², T. Strauss ¹², A. M. Szelc ¹¹, N. Taniuchi⁵, K. Terao ³², C. Thorpe ²¹, D. Torbunov ³, D. Totani ⁴, M. Toups ¹², A. Trettin ²¹, Y.-T. Tsai ³², J. Tyler ¹⁷, M. A. Uchida ⁵, T. Usher ³², B. Viren ³, J. Wang²⁶, M. Weber ², H. Wei ²⁰, A. J. White⁷, S. Wolbers ¹², T. Wongjirad ³⁸, M. Wospakrik¹², K. Wresilo ⁵, W. Wu ²⁹, E. Yandel ^4,19, T. Yang ¹², L. E. Yates ¹², H. W. Yu ³, G. P. Zeller ¹², J. Zennamo ¹², and C. Zhang ³ (MicroBooNE Collaboration^*)

¹Argonne National Laboratory (ANL), Lemont, Illinois 60439, USA
²Universität Bern, Bern CH-3012, Switzerland
³Brookhaven National Laboratory (BNL), Upton, New York 11973, USA
⁴University of California, Santa Barbara, California 93106, USA
⁵University of Cambridge, Cambridge CB3 0HE, United Kingdom
⁶Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid E-28040, Spain
⁷University of Chicago, Chicago, Illinois 60637, USA
⁸University of Cincinnati, Cincinnati, Ohio 45221, USA
⁹Colorado State University, Fort Collins, Colorado 80523, USA
¹⁰Columbia University, New York, New York 10027, USA
¹¹University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
¹²Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510, USA
¹³Universidad de Granada, Granada E-18071, Spain
¹⁴Illinois Institute of Technology (IIT), Chicago, Illinois 60616, USA
¹⁵Imperial College London, London SW7 2AZ, United Kingdom
¹⁶Indiana University, Bloomington, Indiana 47405, USA
¹⁷Kansas State University (KSU), Manhattan, Kansas 66506, USA
¹⁸Lancaster University, Lancaster LA1 4YW, United Kingdom
¹⁹Los Alamos National Laboratory (LANL), Los Alamos, New Mexico 87545, USA
²⁰Louisiana State University, Baton Rouge, Louisiana 70803, USA
²¹The University of Manchester, Manchester M13 9PL, United Kingdom
²²Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA
²³University of Michigan, Ann Arbor, Michigan 48109, USA
²⁴Michigan State University, East Lansing, Michigan 48824, USA
²⁵University of Minnesota, Minneapolis, Minnesota 55455, USA
²⁶Nankai University, Nankai District, Tianjin 300071, China
²⁷New Mexico State University (NMSU), Las Cruces, New Mexico 88003, USA
²⁸University of Oxford, Oxford OX1 3RH, United Kingdom
²⁹University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
³⁰Queen Mary University of London, London E1 4NS, United Kingdom
³¹Rutgers University, Piscataway, New Jersey 08854, USA
³²SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
³³South Dakota School of Mines and Technology (SDSMT), Rapid City, South Dakota 57701, USA
³⁴University of Southern Maine, Portland, Maine 04104, USA
³⁵Syracuse University, Syracuse, New York 13244, USA
³⁶Tel Aviv University, Tel Aviv 69978, Israel
³⁷University of Texas, Arlington, Texas 76019, USA
³⁸Tufts University, Medford, Massachusetts 02155, USA
³⁹Center for Neutrino Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
⁴⁰University of Warwick, Coventry CV4 7AL, United Kingdom

^*Contact author: microboone_info@fnal.gov

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Phys. Rev. Lett. 136, 181806 – Published 7 May, 2026

DOI: https://doi.org/10.1103/89qs-4lcp

Abstract

We present an inclusive search for anomalous production of single-photon events from neutrino interactions in the MicroBooNE experiment. The search and its signal definition are motivated by the previous observation of a low-energy excess of electromagnetic shower events from the MiniBooNE experiment. We use the Wire-Cell reconstruction framework to select a sample of inclusive single-photon final-state interactions with a final efficiency and purity of 7.0% and 40.2%, respectively. We leverage simultaneous measurements of sidebands of charged current $ν_{μ}$ interactions and neutral current interactions producing $π^{0}$ mesons to constrain signal and background predictions and reduce uncertainties. We perform a blind analysis using a dataset collected from February 2016 to July 2018, corresponding to an exposure of $6.34 \times 10^{20}$ protons on target from the Booster Neutrino Beam at Fermilab. In the full signal region, we observe agreement between the data and the prediction, with a goodness-of-fit $p$ value of 0.11. We then isolate a subsample of these events containing no visible protons, and observe $93 \pm 22 (stat) \pm 35 (syst)$ data events above prediction, corresponding to just above $2 σ$ local significance, concentrated at shower energies below 600 MeV.

Physics Subject Headings (PhySH)

Neutrinos

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Supplemental Material

References (49)

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Phys. Rev. Lett. 136, 181806– Published 7 May, 2026

Vol. 136, Iss. 18 — 8 May 2026

Received 14 February 2025
Revised 23 February 2026
Accepted 9 April 2026

DOI: https://doi.org/10.1103/89qs-4lcp

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Inclusive Search for Anomalous Single-Photon Production in MicroBooNE

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Physics Subject Headings (PhySH)

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Supplemental Material

References (49)

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