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Probing the Solar B8 Neutrino Fog with XENONnT

E. Aprile1, J. Aalbers2, K. Abe3, M. M. Abu Rmeileh4, M. Adrover5, S. Ahmed Maouloud6, L. Althueser7, B. Andrieu6, E. Angelino8,9 et al. (XENON Collaboration**)

E. Angelino8,9, D. Antón Martin9, S. R. Armbruster10, F. Arneodo11, L. Baudis5, M. Bazyk12, V. Beligotti8, L. Bellagamba13, R. Biondi8, A. Bismark5, K. Boese10, R. M. Braun7, G. Bruni13, R. Budnik4, C. Cai14, C. Capelli5, J. M. R. Cardoso15, A. P. Cimental Chávez5, A. P. Colijn16, J. Conrad17, J. J. Cuenca-García5, V. D’Andrea8,*, L. C. Daniel Garcia12, M. P. Decowski16, A. Deisting18, C. Di Donato19,8, P. Di Gangi13, S. Diglio12, K. Eitel20, S. el Morabit16, R. Elleboro19,8, A. Elykov20, A. D. Ferella19,8, C. Ferrari8, H. Fischer21, T. Flehmke17, M. Flierman16, R. Frankel4, D. Fuchs17, W. Fulgione22,8, C. Fuselli16, F. Gao14, R. Giacomobono23, F. Girard6, R. Glade-Beucke21, L. Grandi9, J. Grigat21, H. Guan24, M. Guida10, P. Gyorgy18, R. Hammann10, C. Hils18, L. Hoetzsch5, N. F. Hood25, M. Iacovacci23, Y. Itow3, J. Jakob7, F. Joerg5, Y. Kaminaga3, M. Kara20, S. Kazama26, P. Kharbanda16, M. Kobayashi26, D. Koke7, K. Kooshkjalali18, A. Kopec27, E. Kozlova28, H. Landsman4, R. F. Lang24, L. Levinson4, A. Li25, H. Li29, I. Li30, S. Li28, S. Liang30, Z. Liang28, Y.-T. Lin7, S. Lindemann21, M. Lindner10, K. Liu14,†, M. Liu1, F. Lombardi18, J. A. M. Lopes15,‡, G. M. Lucchetti13, T. Luce21, Y. Ma25, C. Macolino19,8, G. C. Madduri21, J. Mahlstedt17, F. Marignetti23, T. Marrodán Undagoitia10, K. Martens3, J. Masbou12, S. Mastroianni23, V. Mazza13, J. Merz18, M. Messina8, A. Michel20, K. Miuchi31, R. Miyata26, A. Molinario22, S. Moriyama3, M. Murra1, J. Müller21, K. Ni25, C. T. Oba Ishikawa3, U. Oberlack18, K. Otsuzuki3, S. Ouahada5, B. Paetsch4, Y. Pan6, Q. Pellegrini6, R. Peres5, J. Pienaar4, M. Pierre16,§, G. Plante1, T. R. Pollmann16, F. Pompa12, A. Prajapati19,8, L. Principe12, J. Qin30, D. Ramírez García5, A. Ravindran12, A. Razeto8, R. Singh24, L. Sanchez30, J. M. F. dos Santos15, I. Sarnoff11, G. Sartorelli13, M. T. Schiller32, P. Schulte7, H. Schulze Eißing7, M. Schumann21, L. Scotto Lavina6, M. Selvi13, F. Semeria13, F. N. Semler21, P. Shagin8, S. Shi1, H. Simgen10, Z. Song29, A. Stevens21, C. Szyszka18, A. Takeda3, Y. Takeuchi31, P.-L. Tan1, D. Thers12, G. Trinchero22, C. D. Tunnell30, K. Valerius20, S. Vecchi33, S. Vetter20, G. Volta10,∥, B. von Krosigk32, C. Weinheimer7, D. Wenz7, C. Wittweg5, V. H. S. Wu20, Y. Xing6, D. Xu1,¶, Z. Xu1, M. Yamashita26, J. Yang28, L. Yang25, J. Ye29, M. Yoshida3, L. Yuan9, G. Zavattini33, Y. Zhao14, M. Zhong25, and T. Zhu3 (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
  • 4Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 7610001, Israel
  • 5Physik-Institut, University of Zürich, 8057 Zürich, Switzerland
  • 6LPNHE, Sorbonne Université, CNRS/IN2P3, 75005 Paris, France
  • 7Institut für Kernphysik, University of Münster, 48149 Münster, Germany
  • 8INFN-Laboratori Nazionali del Gran Sasso and Gran Sasso Science Institute, 67100 L’Aquila, Italy
  • 9Department of Physics, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, University of Chicago, Chicago, Illinois 60637, USA
  • 10Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
  • 11New York University Abu Dhabi-Center for Astro, Particle and Planetary Physics, Abu Dhabi, United Arab Emirates
  • 12SUBATECH, IMT Atlantique, CNRS/IN2P3, Nantes Université, Nantes 44307, France
  • 13Department of Physics and Astronomy, University of Bologna and INFN-Bologna, 40126 Bologna, Italy
  • 14Department of Physics & 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 and Institute of Experimental Particle 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, Bucknell University, Lewisburg, Pennsylvania, USA
  • 28Department of Physics, School of Science, Westlake University, Hangzhou 310030, People’s Republic of China
  • 29School of Science and Engineering, The Chinese University of Hong Kong (Shenzhen), Shenzhen, Guangdong, 518172, People’s Republic of China
  • 30Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
  • 31Department of Physics, Kobe University, Kobe, Hyogo 657-8501, Japan
  • 32Kirchhoff-Institute for Physics, Heidelberg University, 69120 Heidelberg, Germany
  • 33INFN-Ferrara and Dip. di Fisica e Scienze della Terra, Università di Ferrara, 44122 Ferrara, Italy

  • *Also at INFN-Roma Tre, 00146 Roma, Italy.
  • †Contact author: lkx21@mails.tsinghua.edu.cn
  • ‡Also at Coimbra Polytechnic—ISEC, 3030-199 Coimbra, Portugal.
  • §Contact author: maxime.pierre@nikhef.nl
  • ∥Contact author: giovanni.volta@mpi-hd.mpg.de
  • Contact author: dacheng.xu@columbia.edu
  • **Contact author: xenon@lngs.infn.it
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Phys. Rev. Lett. 137, 091807 – Published 28 August, 2026

DOI: https://doi.org/10.1103/xvpn-w3q9

Abstract

We report a 3.3σ measurement of coherent elastic neutrino-nucleus scattering from solar B8 neutrinos using a 6.77  t×yr exposure from the XENONnT experiment, inferring a solar B8 neutrino flux of (5−2+3)×106  cm−2 s−1, consistent with previous measurements. In the presence of the B8 “neutrino fog,” we find no evidence for light dark matter, and observe diminishing returns in sensitivity with increasing exposure. A 93% increase in exposure from the previous search improves the median sensitivity to the nucleon scattering cross section for a 5  GeV/c2 spin-independent weakly interacting massive particle by 10%. The dataset was also used to measure the weak mixing angle at ∼0.02  GeV/c momentum transfer and constrain physics beyond the Standard Model.

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Physics Subject Headings (PhySH)

See Also

Searches for Light Dark Matter and Evidence of Coherent Elastic Neutrino-Nucleus Scattering of Solar Neutrinos with the LUX-ZEPLIN (LZ) Experiment

D. S. Akerib et al. (LZ Collaboration)
Phys. Rev. Lett. 137, 091806 (2026)

Article Text

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Phys. Rev. Lett. 137, 091807– Published 28 August, 2026
  • Received 8 April 2026
  • Revised 9 June 2026
  • Accepted 10 July 2026
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