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Light Dark Matter Search with 7.8 Tonne-Year of Ionization-Only Data in XENONnT

E. Aprile ¹, J. Aalbers ², K. Abe ³, M. Adrover ⁴, S. Ahmed Maouloud ⁵, L. Althueser ⁶, B. Andrieu ⁵, E. Angelino ⁷, D. Antón Martin ⁸ et al. (XENON Collaboration^¶)

D. Antón Martin ⁸, S. R. Armbruster ⁹, F. Arneodo ¹⁰, L. Baudis ⁴, M. Bazyk ¹¹, V. Beligotti⁷, L. Bellagamba ¹², R. Biondi ⁷, A. Bismark ⁴, K. Boese ⁹, R. M. Braun ⁶, G. Bruni ¹², G. Bruno ¹¹, R. Budnik ¹³, C. Cai¹⁴, C. Capelli ⁴, J. M. R. Cardoso ¹⁵, A. P. Cimental Chávez ⁴, A. P. Colijn ¹⁶, J. Conrad ¹⁷, J. J. Cuenca-García⁴, V. D’Andrea ^7,*, L. C. Daniel Garcia ¹¹, M. P. Decowski ¹⁶, A. Deisting ¹⁸, C. Di Donato ^19,7, P. Di Gangi ¹², S. Diglio ¹¹, K. Eitel ²⁰, S. el Morabit ¹⁶, R. Elleboro¹⁹, A. Elykov ²⁰, A. D. Ferella ^19,7, C. Ferrari ⁷, H. Fischer ²¹, T. Flehmke ¹⁷, M. Flierman ¹⁶, R. Frankel ¹³, D. Fuchs ¹⁷, W. Fulgione ^22,7, C. Fuselli ¹⁶, F. Gao ¹⁴, R. Giacomobono ²³, F. Girard ⁵, R. Glade-Beucke ²¹, L. Grandi ⁸, J. Grigat ²¹, H. Guan ²⁴, M. Guida ⁹, P. Gyorgy ¹⁸, R. Hammann ⁹, C. Hils ¹⁸, L. Hoetzsch ⁴, N. F. Hood ²⁵, M. Iacovacci ²³, Y. Itow ²⁶, J. Jakob ⁶, F. Joerg ⁴, Y. Kaminaga ³, M. Kara ²⁰, S. Kazama ²⁶, P. Kharbanda ¹⁶, M. Kobayashi ²⁶, D. Koke ⁶, K. Kooshkjalali¹⁸, A. Kopec ^25,†, H. Landsman ¹³, R. F. Lang ²⁴, L. Levinson ¹³, A. Li ²⁵, I. Li ²⁷, S. Li ²⁸, S. Liang ²⁷, Z. Liang ²⁸, Y.-T. Lin ^9,6, S. Lindemann ²¹, M. Lindner ⁹, K. Liu ¹⁴, M. Liu ¹, F. Lombardi ¹⁸, J. A. M. Lopes ^15,‡, G. M. Lucchetti ¹², T. Luce ²¹, Y. Ma ²⁵, C. Macolino ^19,7, G. C. Madduri ²¹, J. Mahlstedt ¹⁷, F. Marignetti ²³, T. Marrodán Undagoitia ⁹, K. Martens ³, J. Masbou ¹¹, S. Mastroianni ²³, V. Mazza ¹², A. Melchiorre ^19,7, J. Merz ¹⁸, M. Messina ⁷, A. Michel²⁰, K. Miuchi ²⁹, A. Molinario ²², S. Moriyama ³, M. Murra ¹, J. Müller ²¹, K. Ni ²⁵, C. T. Oba Ishikawa ³, U. Oberlack ¹⁸, S. Ouahada ⁴, B. Paetsch ¹³, Y. Pan ^5,§, Q. Pellegrini ⁵, R. Peres ⁴, J. Pienaar ¹³, M. Pierre ¹⁶, G. Plante ¹, T. R. Pollmann ¹⁶, F. Pompa¹¹, A. Prajapati ¹⁹, L. Principe ¹¹, J. Qin ²⁷, D. Ramírez García⁴, A. Ravindran ¹¹, A. Razeto ⁷, R. Singh ²⁴, L. Sanchez ²⁷, J. M. F. dos Santos ¹⁵, I. Sarnoff ¹⁰, G. Sartorelli ¹², J. Schreiner⁹, P. Schulte ⁶, H. Schulze Eißing ⁶, M. Schumann ²¹, L. Scotto Lavina ⁵, M. Selvi ¹², F. Semeria ¹², F. N. Semler ²¹, P. Shagin ¹⁸, S. Shi ^1,∥, H. Simgen ⁹, Z. Song ³⁰, A. Stevens ²¹, C. Szyszka ¹⁸, A. Takeda ³, Y. Takeuchi ²⁹, P.-L. Tan ¹, D. Thers ¹¹, G. Trinchero ²², C. D. Tunnell ²⁷, K. Valerius ²⁰, S. Vecchi ³¹, S. Vetter ²⁰, G. Volta ⁹, B. von Krosigk ³², C. Weinheimer ⁶, M. Weiss ¹³, D. Wenz ⁶, C. Wittweg ⁴, V. H. S. Wu ²⁰, Y. Xing ⁵, D. Xu ¹, Z. Xu ¹, M. Yamashita ³, J. Yang ²⁸, L. Yang ²⁵, J. Ye ³⁰, M. Yoshida ³, L. Yuan ⁸, G. Zavattini ³¹, Y. Zhao ¹⁴, M. Zhong ²⁵, and T. Zhu ³ (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
⁴Physik-Institut, University of Zürich, 8057 Zürich, Switzerland
⁵LPNHE, Sorbonne Université, CNRS/IN2P3, 75005 Paris, France
⁶Institut für Kernphysik, University of Münster, 48149 Münster, Germany
⁷INFN-Laboratori Nazionali del Gran Sasso and Gran Sasso Science Institute, 67100 L’Aquila, Italy
⁸Department of Physics, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, University of Chicago, Chicago, Illinois 60637, USA
⁹Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
¹⁰New York University Abu Dhabi—Center for Astro, Particle and Planetary Physics, Abu Dhabi, United Arab Emirates
¹¹SUBATECH, IMT Atlantique, CNRS/IN2P3, Nantes Université, Nantes 44307, France
¹²Department of Physics and Astronomy, University of Bologna and INFN-Bologna, 40126 Bologna, Italy
¹³Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 7610001, Israel
¹⁴Department of Physics and Center for High Energy Physics, Tsinghua University, Beijing 100084, People’s Republic of China
¹⁵LIBPhys, Department of Physics, University of Coimbra, 3004-516 Coimbra, Portugal
¹⁶Nikhef and the University of Amsterdam, Science Park, 1098XG Amsterdam, Netherlands
¹⁷Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, Stockholm SE-10691, Sweden
¹⁸Institut für Physik and Exzellenzcluster PRISMA⁺, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
¹⁹Department of Physics and Chemistry, University of L’Aquila, 67100 L’Aquila, Italy
²⁰Institute for Astroparticle Physics, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
²¹Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
²²INAF-Astrophysical Observatory of Torino, Department of Physics, University of Torino and INFN-Torino, 10125 Torino, Italy
²³Department of Physics “Ettore Pancini,” University of Napoli and INFN-Napoli, 80126 Napoli, Italy
²⁴Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, 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 and Astronomy, Rice University, Houston, Texas 77005, USA
²⁸Department of Physics, School of Science, Westlake University, Hangzhou 310030, People’s Republic of China
²⁹Department of Physics, Kobe University, Kobe, Hyogo 657-8501, Japan
³⁰School of Science and Engineering, The Chinese University of Hong Kong (Shenzhen), Shenzhen, Guangdong, 518172, People’s Republic of China
³¹INFN-Ferrara and Dipartimento di Fisica e Scienze della Terra, Università di Ferrara, 44122 Ferrara, Italy
³²Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg, Germany

^*Also at INFN-Roma Tre, 00146 Roma, Italy.
^†Present address: Department of Physics and Astronomy, Bucknell University, Lewisburg, Pennsylvania, USA.
^‡Also at Coimbra Polytechnic—ISEC, 3030-199 Coimbra, Portugal.
^§Contact author: yongyu.pan@lpnhe.in2p3.fr
^∥Contact author: shenyang.shi@columbia.edu
^¶Contact author: xenon@lngs.infn.it

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Phys. Rev. Lett. 137, 051003 – Published 30 July, 2026

DOI: https://doi.org/10.1103/2lrq-f6bk

Abstract

We report on a blinded search for dark matter (DM) using ionization-only (S2-only) signals in XENONnT with a total exposure of $7.83 Tonne-year$ over 579 days in three science runs. Dedicated background suppression techniques and the first complete S2-only background model in XENONnT provide sensitivity to nuclear recoils of $[0.5, 5.0] {keV}_{nr}$ and electronic recoils of $[0.04, 0.7] {keV}_{ee}$ . No significant excess over the expected background is observed, and we set 90% confidence level upper limits on spin-independent DM-nucleon and spin-dependent DM-neutron scattering for DM masses between 3 and $8 GeV / c^{2}$ , as well as on DM-electron scattering, axionlike particles, and dark photons, improving on previous constraints. For spin-independent DM-nucleon scattering, we exclude cross sections above $6.0 \times 10^{- 45} {cm}^{2}$ at a DM mass of $5 GeV / c^{2}$ , pushing the XENONnT sensitivity closer to the region where coherent elastic neutrino-nucleus scattering becomes an irreducible background.

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References (72)

E. Aprile et al. (XENON Collaboration), The XENONnT dark matter experiment, Eur. Phys. J. C 84, 784 (2024).
L. Roszkowski, E. M. Sessolo, and S. Trojanowski, WIMP dark matter candidates and searches—Current status and future prospects, Rep. Prog. Phys. 81, 066201 (2018).
G. Jungman, M. Kamionkowski, and K. Griest, Supersymmetric dark matter, Phys. Rep. 267, 195 (1996).
G. Bertone and D. Hooper, History of dark matter, Rev. Mod. Phys. 90, 045002 (2018).
E. Aprile et al. (XENON Collaboration), WIMP dark matter search using a 3.1 tonne-year exposure of the XENONnT experiment, Phys. Rev. Lett. 135, 221003 (2025).
E. Aprile et al. (XENON Collaboration), First search for light dark matter in the neutrino fog with XENONnT, Phys. Rev. Lett. 134, 111802 (2025).
E. Aprile et al. (XENON Collaboration), First indication of solar ${}^{8}B$ neutrinos via coherent elastic neutrino-nucleus scattering with XENONnT, Phys. Rev. Lett. 133, 191002 (2024).
E. Aprile et al. (XENON Collaboration), Light dark matter search with ionization signals in XENON1T, Phys. Rev. Lett. 123, 251801 (2019).
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); 110, 109903(E) (2024).
E. Aprile et al. (XENON Collaboration), Search for light dark matter in low-energy ionization signals from XENONnT, Phys. Rev. Lett. 134, 161004 (2025).
M. Zhang et al. (PandaX Collaboration), Search for light dark matter with 259 days of data in PandaX-4T, Phys. Rev. Lett. 135, 211001 (2025).
S. Li et al. (PandaX Collaboration), Search for light dark matter with ionization signals in the PandaX-4T experiment, Phys. Rev. Lett. 130, 261001 (2023).
E. Aprile and T. Doke, Liquid xenon detectors for particle physics and astrophysics, Rev. Mod. Phys. 82, 2053 (2010).
G. Plante, E. Aprile, J. Howlett, and Y. Zhang, Liquid-phase purification for multi-tonne xenon detectors, Eur. Phys. J. C 82, 860 (2022).
C. M. B. Monteiro, L. M. P. Fernandes, J. A. M. Lopes, L. C. C. Coelho, J. F. C. A. Veloso, J. M. F. d. Santos, K. Giboni, and E. Aprile, Secondary scintillation yield in pure xenon, J. Instrum. 2, P05001 (2007).
E. Aprile et al. (XENON Collaboration), XENONnT WIMP search: Signal and background modeling and statistical inference, Phys. Rev. D 111, 103040 (2025).
M. Szydagis et al., A review of NEST models for liquid xenon and an exhaustive comparison with other approaches, Front. Detect. Sci. Tech. 2, 1480975 (2024).
E. Aprile et al. (XENON Collaboration), The triggerless data acquisition system of the XENONnT experiment, J. Instrum. 18, P07054 (2023).
E. Aprile et al. (XENON100 Collaboration), Observation and applications of single-electron charge signals in the XENON100 experiment, J. Phys. G 41, 035201 (2014).
D. S. Akerib et al. (LZ, LUX Collaborations), Low-energy radon backgrounds from electrode grids in dual-phase xenon TPCs, arXiv:2602.21177.
D. S. Akerib et al. (LZ Collaboration), Study of few-electron backgrounds in the LUX-ZEPLIN detector, Phys. Rev. D 113, 072018 (2026).
E. Aprile et al. (XENON Collaboration), XENONnT analysis: Signal reconstruction, calibration, and event selection, Phys. Rev. D 111, 062006 (2025).
J. D. Lewin and P. F. Smith, Review of mathematics, numerical factors, and corrections for dark matter experiments based on elastic nuclear recoil, Astropart. Phys. 6, 87 (1996).
J. Menendez, D. Gazit, and A. Schwenk, Spin-dependent WIMP scattering off nuclei, Phys. Rev. D 86, 103511 (2012).
D. Baxter et al., Recommended conventions for reporting results from direct dark matter searches, Eur. Phys. J. C 81, 907 (2021).
M. Hoferichter, J. Menéndez, and A. Schwenk, Coherent elastic neutrino-nucleus scattering: EFT analysis and nuclear responses, Phys. Rev. D 102, 074018 (2020).
E. Del Nobile, M. Kaplinghat, and H.-B. Yu, Direct detection signatures of self-interacting dark matter with a light mediator, J. Cosmol. Astropart. Phys. 10 (2015) 055.
N. Fornengo, P. Panci, and M. Regis, Long-range forces in direct dark matter searches, Phys. Rev. D 84, 115002 (2011).
R. Essig, A. Manalaysay, J. Mardon, P. Sorensen, and T. Volansky, First direct detection limits on sub-GeV dark matter from XENON10, Phys. Rev. Lett. 109, 021301 (2012).
R. Essig, T. Volansky, and T.-T. Yu, New constraints and prospects for sub-GeV dark matter scattering off electrons in xenon, Phys. Rev. D 96, 043017 (2017).
A. R. Caddell, V. V. Flambaum, and B. M. Roberts, Accurate electron-recoil ionization factors for dark matter direct detection in xenon, krypton, and argon, Phys. Rev. D 108, 083030 (2023).
J. Aalbers, B. Pelssers, J. R. Angevaare, and K. D. Morå, JelleAalbers/wimprates: v0.5.0, Zenodo (2023), 10.5281/zenodo.7636982.
M. Pospelov, A. Ritz, and M. B. Voloshin, Bosonic super-WIMPs as keV-scale dark matter, Phys. Rev. D 78, 115012 (2008).
I. M. Bloch, R. Essig, K. Tobioka, T. Volansky, and T.-T. Yu, Searching for dark absorption with direct detection experiments, J. High Energy Phys. 06 (2017) 087.
B. L. Henke, E. M. Gullikson, and J. C. Davis, X-ray interactions: Photoabsorption, scattering, transmission, and reflection at $E = 50 - 30, 00 eV$ , $Z = 1 - 92 Atom$ , Data Nucl. Data Tables 54, 181 (1993).
E. Aprile et al. (XENON Collaboration), Low-energy nuclear recoil calibration of XENONnT with a ${}^{88}{YBe}$ photoneutron source, arXiv:2412.10451.
J. I. Collar, Applications of an ${}^{88}Y / B e$ photo-neutron calibration source to dark matter and neutrino experiments, Phys. Rev. Lett. 110, 211101 (2013).
XENONnT Collaboration, xenon-fuse: Framework for unified simulations of events (version 1.6.0), available from https://github.com/XENONnT/fuse (2025).
J. Aalbers et al., AxFoundation/strax: Stream analysis for xenon TPCs, 10.5281/zenodo.11355772 (2024).
XENONnT Collaboration, XENONnT/straxen: Streaming analysis for xenon, 10.5281/zenodo.12608732 (2024).
E. Aprile et al. (XENON Collaboration), XENONnT analysis: Signal reconstruction, calibration and event selection, Phys. Rev. D 111, 062006 (2025).
E. Aprile et al. (XENON Collaboration), Intrinsic backgrounds from Rn and Kr in the XENON100 experiment, Eur. Phys. J. C 78, 132 (2018).
R. E. Linehan, High voltage electrode development and the LZ experiment’s WIMP search, Ph.D. thesis, Stanford University, 2022.
P. Sorensen, Anisotropic diffusion of electrons in liquid xenon with application to improving the sensitivity of direct dark matter searches, Nucl. Instrum. Methods Phys. Res., Sect. A 635, 41 (2011).
E. Aprile et al. (XENON Collaboration), Material radiopurity control in the XENONnT experiment, Eur. Phys. J. C 82, 599 (2022).
D. S. Akerib et al. (LUX Collaboration), Investigation of background electron emission in the LUX detector, Phys. Rev. D 102, 092004 (2020).
G. Papamakarios, E. Nalisnick, D. J. Rezende, S. Mohamed, and B. Lakshminarayanan, Normalizing flows for probabilistic modeling and inference, J. Mach. Learn. Res. 22, 1 (2021) [arXiv:1912.02762].
A. Paszke, S. Gross, F. Massa, A. Lerer, J. Bradbury, G. Chanan, T. Killeen, Z. Lin, N. Gimelshein, L. Antiga, A. Desmaison, A. Köpf, E. Z. Yang, Z. DeVito, M. Raison, A. Tejani, S. Chilamkurthy, B. Steiner, L. Fang, J. Bai, and S. Chintala, pytorch: An imperative style, high-performance deep learning library, arXiv:1912.01703.
C. Durkan, A. Bekasov, I. Murray, and G. Papamakarios, nflows: Normalizing flows in pytorch, 10.5281/zenodo.4296287 (2020).
M. Abadi et al., tensorflow: Large-scale machine learning on heterogeneous systems, software available from https://www.tensorflow.org/ (2015).
E. Aprile et al. (XENON Collaboration), Low-energy calibration of XENON1T with an internal ${}^{37}{Ar}$ source, Eur. Phys. J. C 83, 542 (2023).
F. Jörg, S. Li, J. Schreiner, H. Simgen, and R. F. Lang, Characterization of a ${}^{220}{Rn}$ source for low-energy electronic recoil calibration of the XENONnT detector, J. Instrum. 18, P11009 (2023).
E. Aprile et al. (XENON Collaboration), Spectral measurement of the ${}^{214}{Bi}$ beta-decay to the ${}^{214}{Po}$ ground state with XENONnT, Phys. Rev. C 113, 044303 (2026).
F. Jörg, G. Eurin, and H. Simgen, Production and characterization of a ${}^{222}{Rn}$ -emanating stainless steel source, Appl. Radiat. Isot. 194, 110666 (2023).
C. Krause and D. Shih, Fast and accurate simulations of calorimeter showers with normalizing flows, Phys. Rev. D 107, 113003 (2023).
Z. Bo et al. (PandaX Collaboration), First indication of solar ${}^{8}B$ neutrinos through coherent elastic neutrino-nucleus scattering in PandaX-4T, Phys. Rev. Lett. 133, 191001 (2024).
B. Aharmim et al. (SNO Collaboration), Combined analysis of all three phases of solar neutrino data from the Sudbury Neutrino Observatory, Phys. Rev. C 88, 025501 (2013).
XENONnT Collaboration, XENONnT/alea: v0.3.4 (2025), 10.5281/zenodo.18840642.
G. J. Feldman and R. D. Cousins, A unified approach to the classical statistical analysis of small signals, Phys. Rev. D 57, 3873 (1998).
G. Cowan, K. Cranmer, E. Gross, and O. Vitells, Power-constrained limits, arXiv:1105.3166.
J. Angle et al. (XENON10 Collaboration), A search for light dark matter in XENON10 data, Phys. Rev. Lett. 107, 051301 (2011); 110, 249901(E) (2013).
E. Aprile et al. (XENON Collaboration), Search for new physics in electronic recoil data from XENONnT, Phys. Rev. Lett. 129, 161805 (2022).
J. Aalbers et al. (LZ Collaboration), Search for new physics in low-energy electron recoils from the first LZ exposure, Phys. Rev. D 108, 072006 (2023).
P. Agnes et al. (DarkSide-50 Collaboration), Search for low-mass dark matter WIMPs with 12 ton-day exposure of DarkSide-50, Phys. Rev. D 107, 063001 (2023).
P. Agnes et al. (DarkSide Collaboration), Search for dark matter particle interactions with electron final states with DarkSide-50, Phys. Rev. Lett. 130, 101002 (2023).
T. Aralis et al. (SuperCDMS Collaboration), Constraints on dark photons and axionlike particles from the SuperCDMS Soudan experiment, Phys. Rev. D 101, 052008 (2020); 103, 039901(E) (2021).
C. A. J. O’Hare, New definition of the neutrino floor for direct dark matter searches, Phys. Rev. Lett. 127, 251802 (2021).
D. Baxter, R. Essig, Y. Hochberg, M. Kaznacheeva, B. von Krosigk, F. Reindl, R. K. Romani, and F. Wagner, Low-energy backgrounds in solid-state phonon and charge detectors, Annu. Rev. Nucl. Part. Sci. 75, 301 (2025).
J. Aalbers et al. (XLZD Collaboration), The XLZD design book: Towards the next-generation liquid xenon observatory for dark matter and neutrino physics, Eur. Phys. J. C 85, 1192 (2025).
A. Abdukerim et al. (PandaX Collaboration), PandaX-xT—A deep underground multi-ten-tonne liquid xenon observatory, Sci. China Phys. Mech. Astron. 68, 221011 (2025).
D. S. Akerib et al. (LZ Collaboration), Searches for light dark matter and evidence of coherent elastic neutrino-nucleus scattering of solar neutrinos with the LUX-ZEPLIN (LZ) experiment, arXiv:2512.08065.
XENON Collaboration, XENONnT S2-only data release, 10.5281/zenodo.19687011 (2026).

Phys. Rev. Lett. 137, 051003– Published 30 July, 2026

Vol. 137, Iss. 5 — 31 July 2026

Received 18 January 2026
Accepted 11 June 2026

DOI: https://doi.org/10.1103/2lrq-f6bk

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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Light Dark Matter Search with 7.8 Tonne-Year of Ionization-Only Data in XENONnT

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