Neutron detector response modeling in NOvA
Abstract
Neutrons can present a significant challenge for neutrino experiments in which energy reconstruction is critical. With the ability to escape detection completely and with a weak correlation between their kinetic energy and any eventual energy deposition, it is difficult to fully account for neutrons produced in neutrino interactions. This in turn leads to significant model dependence when evaluating neutron-related systematic uncertainties. The NOvA experiment is a long-baseline neutrino oscillation experiment with a high-statistics sample of antineutrino data collected by its near detector. We report an excess relative to data of simulated neutron candidates with low energy depositions when using standard Geant4 physics lists. The simulation excess is traced to an overabundance of secondary photons produced from interactions of neutrons with kinetic energy greater than \SI{20}{\mega\eV}. Improved agreement with data is obtained by applying the data-driven neutron-on-carbon \menate model for neutrons between \SI{20}{\mega\eV} and ∼\SI{100}{\mega\eV}. With \menate, the residual oversimulation is more uniform across the calorimetric neutron energy spectrum, suggesting possible overproduction of primary neutrons by the GENIE neutrino interaction generator. These results motivate the adoption of \menate-supplemented Geant4 simulation as the nominal simulation in the production of future \nova simulation.
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BibTeX
@misc{collaboration2026neutron,
title = {{Neutron detector response modeling in NOvA}},
author = {NOvA Collaboration and S. Abubakar and M. A. Acero and B. Acharya and P. Adamson and N. Anfimov and A. Antoshkin and E. Arrieta-Diaz and L. Asquith and A. Aurisano and A. Back and N. Balashov and P. Baldi and B. A. Bambah and E. F. Bannister and A. Barros and J. Barrow and A. Bat and T. J. C. Bezerra and V. Bhatnagar and B. Bhuyan and J. Bian and A. C. Booth and B. Brahma and C. Bromberg and N. Buchanan and J. Burns and A. Butkevich and E. Catano-Mur and J. P. Cesar and C. Chang and S. Chaudhary and H. Chen and S. Choate and B. C. Choudhary and O. T. K. Chow and A. Christensen and M. F. Cicala and T. E. Coan and T. Contreras and A. Cooleybeck and L. Cremonesi and G. S. Davies and P. F. Derwent and K. Dever and Z. Djurcic and K. Dobbs and D. Dueñas Tonguino and E. C. Dukes and A. Dye and R. Ehrlich and E. Ewart and P. Filip and M. J. Frank and H. R. Gallagher and A. Giri and R. A. Gomes and M. C. Goodman and R. Group and A. Gusmão},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.06956},
eprint = {2609.06956},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.06956},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Neutron detector response modeling in NOvA
AU - NOvA Collaboration
AU - S. Abubakar
AU - M. A. Acero
AU - B. Acharya
AU - P. Adamson
AU - N. Anfimov
AU - A. Antoshkin
AU - E. Arrieta-Diaz
AU - L. Asquith
AU - A. Aurisano
AU - A. Back
AU - N. Balashov
AU - P. Baldi
AU - B. A. Bambah
AU - E. F. Bannister
AU - A. Barros
AU - J. Barrow
AU - A. Bat
AU - T. J. C. Bezerra
AU - V. Bhatnagar
AU - B. Bhuyan
AU - J. Bian
AU - A. C. Booth
AU - B. Brahma
AU - C. Bromberg
AU - N. Buchanan
AU - J. Burns
AU - A. Butkevich
AU - E. Catano-Mur
AU - J. P. Cesar
AU - C. Chang
AU - S. Chaudhary
AU - H. Chen
AU - S. Choate
AU - B. C. Choudhary
AU - O. T. K. Chow
AU - A. Christensen
AU - M. F. Cicala
AU - T. E. Coan
AU - T. Contreras
AU - A. Cooleybeck
AU - L. Cremonesi
AU - G. S. Davies
AU - P. F. Derwent
AU - K. Dever
AU - Z. Djurcic
AU - K. Dobbs
AU - D. Dueñas Tonguino
AU - E. C. Dukes
AU - A. Dye
AU - R. Ehrlich
AU - E. Ewart
AU - P. Filip
AU - M. J. Frank
AU - H. R. Gallagher
AU - A. Giri
AU - R. A. Gomes
AU - M. C. Goodman
AU - R. Group
AU - A. Gusmão
PY - 2026
DA - 2026/09/07
PB - arXiv
DO - 10.48550/arxiv.2609.06956
UR - https://arxiv.org/abs/2609.06956
AB - Neutrons can present a significant challenge for neutrino experiments in which energy reconstruction is critical. With the ability to escape detection completely and with a weak correlation between their kinetic energy and any eventual energy deposition, it is difficult to fully account for neutrons produced in neutrino interactions. This in turn leads to significant model dependence when evaluating neutron-related systematic uncertainties. The NOvA experiment is a long-baseline neutrino oscillation experiment with a high-statistics sample of antineutrino data collected by its near detector. We report an excess relative to data of simulated neutron candidates with low energy depositions when using standard Geant4 physics lists. The simulation excess is traced to an overabundance of secondary photons produced from interactions of neutrons with kinetic energy greater than \SI{20}{\mega\eV}. Improved agreement with data is obtained by applying the data-driven neutron-on-carbon \menate model for neutrons between \SI{20}{\mega\eV} and ∼\SI{100}{\mega\eV}. With \menate, the residual oversimulation is more uniform across the calorimetric neutron energy spectrum, suggesting possible overproduction of primary neutrons by the GENIE neutrino interaction generator. These results motivate the adoption of \menate-supplemented Geant4 simulation as the nominal simulation in the production of future \nova simulation.
ER -