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Low-energy nuclear recoil calibration of XENONnT with a Y88Be photoneutron source

E. Aprile1, J. Aalbers2, K. Abe3, S. Ahmed Maouloud4, L. Althueser4, B. Andrieu4, E. Angelino5,6, D. Antón Martin7, F. Arneodo8 et al. (XENON Collaboration‡‡)

F. Arneodo8, L. Baudis9, M. Bazyk10, L. Bellagamba11, R. Biondi12,*, A. Bismark9, K. Boese12, A. Brown13, G. Bruno10, R. Budnik14, C. Cai15, C. Capelli9, J. M. R. Cardoso16, A. P. Cimental Chávez9, A. P. Colijn17, J. Conrad18, J. J. Cuenca-García9, V. D’Andrea6,†, L. C. Daniel Garcia4, M. P. Decowski17, A. Deisting19, C. Di Donato20,6, P. Di Gangi11, S. Diglio10, K. Eitel21, S. el Morabit17, A. Elykov21, A. D. Ferella20,6, C. Ferrari6, H. Fischer13, T. Flehmke18, M. Flierman17, W. Fulgione5,6, C. Fuselli17, P. Gaemers17, R. Gaior4, M. Galloway9, F. Gao15, S. Ghosh22,‡, R. Giacomobono23, R. Glade-Beucke13, L. Grandi7, J. Grigat13, H. Guan22,§, M. Guida12, P. Gyorgy19, R. Hammann12, A. Higuera24, C. Hils19, L. Hoetzsch12, N. F. Hood25, M. Iacovacci23, Y. Itow26, J. Jakob12,9, F. Joerg12,9, Y. Kaminaga3, M. Kara21, P. Kavrigin14, S. Kazama26, P. Kharbanda17, M. Kobayashi26, D. Koke25, A. Kopec25,∥, H. Landsman14, R. F. Lang22, L. Levinson14, I. Li24, S. Li27,¶, S. Liang24, Z. Liang27, Y.-T. Lin12, S. Lindemann13, M. Lindner12, K. Liu15, M. Liu1,15, J. Loizeau10, F. Lombardi19, J. Long7, J. A. M. Lopes16,**, T. Luce13, Y. Ma25, C. Macolino20,6, J. Mahlstedt18, A. Mancuso11, L. Manenti8, F. Marignetti23, T. Marrodán Undagoitia12, K. Martens3, J. Masbou10, E. Masson4, S. Mastroianni23, A. Melchiorre20,6, J. Merz19, M. Messina6, A. Michael28, K. Miuchi28, A. Molinario5, S. Moriyama3, K. Morå1, Y. Mosbacher14, M. Murra1, J. Müller13, K. Ni25, U. Oberlack19, B. Paetsch14, Y. Pan4, Q. Pellegrini4, R. Peres9, C. Peters24, J. Pienaar7,14, M. Pierre17, G. Plante1, T. R. Pollmann17, L. Principe10, J. Qi25, J. Qin24,††, D. Ramírez García9, M. Rajado9, R. Singh22, L. Sanchez24, J. M. F. dos Santos16, I. Sarnoff8, G. Sartorelli11, J. Schreiner12, P. Schulte13, H. Schulze Eißing13, M. Schumann13, L. Scotto Lavina4, M. Selvi11, F. Semeria11, P. Shagin19, S. Shi1, J. Shi15, M. Silva16, H. Simgen12, C. Szyszka19, A. Takeda3, Y. Takeuchi28, P.-L. Tan18,1, D. Thers10, F. Toschi21, G. Trinchero5, C. D. Tunnell24, F. Tönnies13, K. Valerius21, S. Vecchi29, S. Vetter21, F. I. Villazon Solar19, G. Volta12, C. Weinheimer14, M. Weiss14, D. Wenz9, C. Wittweg9, V. H. S. Wu21, Y. Xing10, D. Xu1, Z. Xu1, M. Yamashita3, L. Yang25, J. Ye30, L. Yuan7, G. Zavattini29, and M. Zhong25 (XENON Collaboration‡‡)

  • 1Physics Department, Columbia University, New York, New York 10027, USA
  • 2Nikhef and the University of Groningen, Van Swinderen Institute, 9747AG Groningen, Netherlands
  • 3Kamioka Observatory, Institute for Cosmic Ray Research and Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205, Japan
  • 4LPNHE, Sorbonne Université, CNRS/IN2P3, 75005 Paris, France
  • 5INAF-Astrophysical Observatory of Torino, Department of Physics, University of Torino and INFN-Torino, 10125 Torino, Italy
  • 6INFN-Laboratori Nazionali del Gran Sasso and Gran Sasso Science Institute, 67100 L’Aquila, Italy
  • 7Department of Physics, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, University of Chicago, Chicago, Illinois 60637, USA
  • 8New York University Abu Dhabi—Center for Astro, Particle and Planetary Physics, Abu Dhabi, United Arab Emirates
  • 9Physik-Institut, University of Zürich, 8057 Zürich, Switzerland
  • 10SUBATECH, IMT Atlantique, CNRS/IN2P3, Nantes Université, Nantes 44307, France
  • 11Department of Physics and Astronomy, University of Bologna and INFN-Bologna, 40126 Bologna, Italy
  • 12Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
  • 13Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
  • 14Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 7610001, Israel
  • 15Department of Physics and Center for High Energy Physics, Tsinghua University, Beijing 100084, People’s Republic of China
  • 16LIBPhys, Department of Physics, University of Coimbra, 3004-516 Coimbra, Portugal
  • 17Nikhef and the University of Amsterdam, Science Park, 1098XG Amsterdam, Netherlands
  • 18Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, Stockholm SE-10691, Sweden
  • 19Institut für Physik & Exzellenzcluster PRISMA+, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
  • 20Department of Physics and Chemistry, University of L’Aquila, 67100 L’Aquila, Italy
  • 21Institute for Astroparticle Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
  • 22Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
  • 23Department of Physics “Ettore Pancini”, University of Napoli and INFN-Napoli, 80126 Napoli, Italy
  • 24Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
  • 25Department of Physics, University of California San Diego, La Jolla, California 92093, USA
  • 26Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, and Institute for Space-Earth Environmental Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
  • 27Department of Physics, School of Science, Westlake University, Hangzhou 310030, People’s Republic of China
  • 28Department of Physics, Kobe University, Kobe, Hyogo 657-8501, Japan
  • 29INFN-Ferrara and Dip. di Fisica e Scienze della Terra, Università di Ferrara, 44122 Ferrara, Italy
  • 30School of Science and Engineering, The Chinese University of Hong Kong (Shenzhen), Shenzhen, Guangdong, 518172, People’s Republic of China

  • *Contact author: riccardo.biondi@lngs.infn.it
  • †Also at INFN-Roma Tre, 00146 Roma, Italy.
  • ‡Contact author: ghosh116@purdue.edu
  • §Contact author: guan81@purdue.edu
  • ∥Now at Department of Physics and Astronomy, Bucknell University, Lewisburg, Pennsylvania, USA.
  • Contact author: lishengchao@westlake.edu.cn
  • **Also at Coimbra Polytechnic—ISEC, 3030-199 Coimbra, Portugal.
  • ††Contact author: qinjuehang@rice.edu
  • ‡‡Contact author: xenon@lngs.infn.it
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Phys. Rev. D 113, 112017 – Published 29 June, 2026

DOI: https://doi.org/10.1103/rsl9-j1ky

Abstract

Characterizing low-energy, keV-range nuclear recoils near the detector threshold is one of the major challenges for large direct dark matter detectors. To that end, we have successfully used an Yttrium-Beryllium photoneutron source that emits 152 keV neutrons for the calibration of the light and charge yields of the XENONnT experiment for the first time. After data selection, we accumulated 474 events from 183 hours of exposure with this source. The expected background was 55±12 accidental coincidence events, estimated using a dedicated 152 hour background calibration run with a Yttrium-PVC gamma-only source and data-driven modeling. From these calibrations, we extracted the light (charge) yield for liquid xenon at our field strength of 23  V/cm between 0.3 (0.7) keVNR and 5.0  keVNR. This calibration is crucial for accurately measuring the solar B8 neutrino coherent elastic neutrino-nucleus scattering and searching for light dark matter particles with masses below 12  GeV/c2.

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References (44)

  1. C. A. J. O’Hare, New definition of the neutrino floor for direct dark matter searches, Phys. Rev. Lett. 127, 251802 (2021).
  2. D. Z. Freedman, Coherent effects of a weak neutral current, Phys. Rev. D 9, 1389 (1974).
  3. V. B. Kopeliovich and L. L. Frankfurt, Isotopic and chiral structure of neutral current, JETP Lett. 19, 145 (1974).
  4. E. Aprile et al. (XENON Collaboration), First indication of solar B8 neutrinos via coherent elastic neutrino-nucleus scattering with XENONnT, Phys. Rev. Lett. 133, 191002 (2024).
  5. Z. Bo et al. (PandaX Collaboration), First indication of solar B8 neutrinos through coherent elastic neutrino-nucleus scattering in PandaX-4T, Phys. Rev. Lett. 133, 191001 (2024).
  6. D. E. Kaplan, M. A. Luty, and K. M. Zurek, Asymmetric dark matter, Phys. Rev. D 79, 115016 (2009).
  7. S. Tulin and H.-B. Yu, Dark matter self-interactions and small scale structure, Phys. Rep. 730, 1 (2018).
  8. E. Aprile et al. (XENON Collaboration), First search for light dark matter in the neutrino fog with XENONnT, Phys. Rev. Lett. 134, 111802 (2025).
  9. E. Aprile et al. (XENON Collaboration), The XENONnT dark matter experiment, Eur. Phys. J. C 84, 784 (2024).
  10. E. Aprile et al. (XENON Collaboration), XENONnT analysis: Signal reconstruction, calibration and event selection, Phys. Rev. D 111, 062006 (2025).
  11. E. Aprile et al. (XENON Collaboration), XENONnT WIMP search: Signal & background modeling and statistical inference, Phys. Rev. D 111, 103040 (2025).
  12. J. I. Collar, Applications of an Y88/Be photo-neutron calibration source to dark matter and neutrino experiments, Phys. Rev. Lett. 110, 211101 (2013).
  13. A. E. Robinson, Reanalysis of radioisotope measurements of the Be9(γ,n)Be8 cross-section, Phys. Rev. C 94, 024613 (2016).
  14. E. Aprile, A. E. Bolotnikov, A. I. Bolozdynya, and T. Doke, Noble Gas Detectors (Wiley-VCH Verlag, Weinheim, Germany, 2006), pp. 42–45.
  15. Hunter, Carter, and Christophorou, Low-energy electron drift and scattering in krypton and xenon, Phys. Rev. A 38 11, 5539 (1988).
  16. E. Aprile et al. (XENON Collaboration), First dark matter search with nuclear recoils from the XENONnT experiment, Phys. Rev. Lett. 131, 041003 (2023).
  17. J. Qin, Computational techniques for the direct detection of dark matter, Ph.D. thesis, Purdue University, 2023.
  18. J. Aalbers et al. (LZ Collaboration), The design, implementation, and performance of the LZ calibration systems, J. Instrum. 19, P08027 (2024).
  19. R. L. Workman et al. (Particle Data Group), Review of particle physics, Prog. Theor. Exp. Phys. 2022, 083C01 (2022).
  20. S. Agostinelli et al. (GEANT4 Collaboration), GEANT4–a simulation toolkit, Nucl. Instrum. Methods Phys. Res., Sect. A 506, 250 (2003).
  21. E. Aprile et al. (XENON Collaboration), Emission of single and few electrons in XENON1T and limits on light dark matter, Phys. Rev. D 106, 022001 (2022).
  22. D. Y. Akimov et al., Observation of delayed electron emission in a two-phase liquid xenon detector, J. Instrum. 11, C03007 (2016).
  23. N. F. Bell et al., Observing the Migdal effect from nuclear recoils of neutral particles with liquid xenon and argon detectors, Phys. Rev. D 105, 096015 (2022).
  24. K. Shibata et al., Jendl-4.0: A new library for nuclear science and engineering, J. Nucl. Sci. Technol. 48, 1 (2011).
  25. E. Aprile et al. (XENONnT Collaboration), Design and performance of the field cage for the XENONnT experiment, Eur. Phys. J. C 84, 138 (2024).
  26. XENON Collaboration, XENONnT/axidence: Strax- based data-driven accidental coincidence background simulation and peak-level salting (2024).
  27. T. Chen and C. Guestrin, XGBoost: A scalable tree boosting system, in Proceedings of the 22nd ACM SIGKDD International Conference on Knowledge Discovery and Data Mining, KDD ’16 (ACM, New York, 2016), pp. 785–794.
  28. E. Aprile et al. (XENON Collaboration), Wfsim: The xenon waveform simulator, https://github.com/XENONnT/WFSim (2021).
  29. XENON Collaboration, XENONnT/appletree: A high-performance program simulates and fits response of xenon (2024).
  30. M. Szydagis et al., A review of nest models for liquid xenon and an exhaustive comparison with other approaches, arXiv:2211.10726.
  31. XENON Collaboration, XENONnT/saltax (2024).
  32. D. Wenz, H. S. Eißing, P. Kavrigin, J. R. Angevaare, A. Terliuk, K. Mizukoshi, P. Gaemers, and S. Shi, Xenonnt/epix: v0.3.4 (2023).
  33. Geant4 Collaboration, Guide for Physics Lists, Geant4 11.4 documentation (2022), https://geant4.web.cern.ch/documentation/dev/plg_html/PhysicsListGuide/index.html.
  34. D. Foreman-Mackey, D. W. Hogg, D. Lang, and J. Goodman, emcee: The MCMC hammer, Publ. Astron. Soc. Pac. 125, 306 (2013).
  35. D. Foreman-Mackey et al., emcee v3: A python ensemble sampling toolkit for affine-invariant MCMC, J. Open Source Software 4, 1864 (2019).
  36. S. Baker and R. D. Cousins, Clarification of the use of CHI square and likelihood functions in fits to histograms, Nucl. Instrum. Methods 221, 437 (1984).
  37. XENON Collaboration, XENONnT/gofevaluation (2024).
  38. B. Lenardo et al., Measurement of the ionization yield from nuclear recoils in liquid xenon between 0.3–6 keV with single-ionization-electron sensitivity, arXiv:1908.00518.
  39. D. S. Akerib et al. (LUX Collaboration), Low-energy (0.7–74 keV) nuclear recoil calibration of the LUX dark matter experiment using D-D neutron scattering kinematics, arXiv:1608.05381.
  40. D. S. Akerib et al. (LUX Collaboration), Improved dark matter search sensitivity resulting from LUX low-energy nuclear recoil calibration, Phys. Rev. Lett. 134, 061002 (2025).
  41. A. Manzur et al., Scintillation efficiency and ionization yield of liquid xenon for mono-energetic nuclear recoils down to 4 keV, Phys. Rev. C 81, 025808 (2010).
  42. G. Plante et al., New measurement of the scintillation efficiency of low-energy nuclear recoils in liquid xenon, Phys. Rev. C 84, 045805 (2011).
  43. B. Hamermesh, M. Hamermesh, and A. Wattenberg, The angular distribution of the photo-neutrons from beryllium, Phys. Rev. 76, 611 (1949).
  44. M. Szydagis, J. Balajthy, G. Block, J. Brodsky, J. Cutter, S. Farrell, J. Huang, E. Kozlova, B. Lenardo, A. Manalaysay, D. McKinsey, M. Mooney, J. Mueller, K. Ni, G. Rischbieter, M. Tripathi, C. Tunnell, V. Velan, and Z. Zhao, Noble element simulation technique (2022).

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Phys. Rev. D 113, 112017– Published 29 June, 2026
  • Received 16 December 2024
  • Accepted 17 April 2026
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