Searches for Light Dark Matter and Evidence of Coherent Elastic Neutrino-Nucleus Scattering of Solar Neutrinos with the LUX-ZEPLIN (LZ) Experiment
SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（卡弗里粒子天体物理与宇宙学研究所，斯坦福大学）；University College London (UCL)（伦敦大学学院）；Brown University（布朗大学）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；University of Zurich（苏黎世大学）；Imperial College London（帝国理工学院）；STFC Rutherford Appleton Laboratory (RAL)（STFC鲁瑟福阿普尔顿实验室）；University of Maryland（马里兰大学）
D. S. Akerib, A. K. Al Musalhi, F. Alder, B. J. Almquist, C. S. Amarasinghe, A. Ames, T. J. Anderson, N. Angelides, H. M. Araújo, J. E. Armstrong, M. Arthurs, A… 展开作者
D. S. Akerib, A. K. Al Musalhi, F. Alder, B. J. Almquist, C. S. Amarasinghe, A. Ames, T. J. Anderson, N. Angelides, H. M. Araújo, J. E. Armstrong, M. Arthurs, A. Baker, S. Balashov, J. Bang, J. W. Bargemann, E. E. Barillier, J. Barthel, D. Bauer, K. Beattie, A. Bhatti, T. P. Biesiadzinski, H. J. Birch, E. Bishop, G. M. Blockinger, C. A. J. Brew, P. Brás, S. Burdin, M. C. Carmona-Benitez, M. Carter, A. Chawla, H. Chen, Y. T. Chin, N. I. Chott, S. Contreras, M. V. Converse, R. Coronel, A. Cottle, G. Cox, D. Curran, C. E. Dahl, I. Darlington, S. Dave, A. David, J. Davis, J. Delgaudio, S. Dey, L. de Viveiros, L. Di Felice, C. Ding, J. E. Y. Dobson, E. Druszkiewicz, S. Dubey, C. L. Dunbar, S. R. Eriksen, S. Fayer, N. M. Fearon, N. Fieldhouse, S. Fiorucci, H. Flaecher, E. D. Fraser, T. M. A. Fruth, P. W. Gaemers, R. J. Gaitskell, A. Geffre, J. Genovesi, C. Ghag, J. Ghamsari, A. Ghosh, S. Ghosh, R. Gibbons, S. Gokhale, J. Green, M. G. D. van der Grinten, J. J. Haiston, C. R. Hall, T. Hall, R. N Hampp, S. J. Haselschwardt, M. A. Hernandez, S. A. Hertel, G. J. Homenides, M. Horn, D. Q. Huang, D. Hunt, E. Jacquet, R. S. James, K. Jenkins, A. C. Kaboth, A. C. Kamaha, M. K. Kannichankandy, D. Khaitan, A. Khazov, J. Kim, Y. D. Kim, D. Kodroff, E. V. Korolkova, H. Kraus, S. Kravitz, L. Kreczko, V. A. Kudryavtsev, C. Lawes, D. S. Leonard, K. T. Lesko, C. Levy, J. Lin, A. Lindote, W. H. Lippincott, J. Long, M. I. Lopes, W. Lorenzon, C. Lu, D. Lucero, S. Luitz, W. Ma, V. Mahajan, P. A. Majewski, A. Manalaysay, R. L. Mannino, R. J. Matheson, C. Maupin, M. E. McCarthy, D. N. McKinsey, J. McLaughlin, J. B. McLaughlin, R. McMonigle, B. Mitra, E. Mizrachi, M. E. Monzani, K. Morå, E. Morrison, B. J. Mount, M. Murdy, A. St. J. Murphy, H. N. Nelson, F. Neves, A. Nguyen, C. L. O'Brien, F. H. O'Shea, I. Olcina, K. C. Oliver-Mallory, J. Orpwood, K. Y Oyulmaz, K. J. Palladino, N. J. Pannifer, N. Parveen, S. J. Patton, B. Penning, G. Pereira, E. Perry, T. Pershing, A. Piepke, S. S. Poudel, Y. Qie, J. Reichenbacher, C. A. Rhyne, G. R. C. Rischbieter, E. Ritchey, H. S. Riyat, R. Rosero, N. J. Rowe, T. Rushton, D. Rynders, S. Saltão, D. Santone, I. Sargeant, A. B. M. R. Sazzad, R. W. Schnee, G. Sehr, B. Shafer, S. Shaw, W. Sherman, K. Shi, T. Shutt, C. Silva, G. Sinev, J. Siniscalco, A. M. Slivar, R. Smith, V. N. Solovov, P. Sorensen, J. Soria, T. J. Sumner, A. Swain, M. Szydagis, D. J. Taylor, D. R. Tiedt, M. Timalsina, D. R. Tovey, J. Tranter, M. Trask, K. Trengove, M. Tripathi, A. Usón, A. C. Vaitkus, O. Valentino, V. Velan, A. Wang, J. J. Wang, Y. Wang, L. Weeldreyer, T. J. Whitis, K. Wild, M. Williams, J. Winnicki, L. Wolf, F. L. H. Wolfs, S. Woodford, D. Woodward, C. J. Wright, Q. Xia, J. Xu, Y. Xu, M. Yeh, D. Yeum, J. Young, W. Zha, H. Zhang, T. Zhang, Y. Zhou
备注：
9 pages, 5 page supplement, 8 total figures, 2 tables. The corresponding data release can be found on HEPData, see http://doi.org/10.17182/hepdata.167350. Accepted to PRL
We present searches for light dark matter (DM) with masses 3-9 GeV/$c^2$ in the presence of coherent elastic neutrino-nucleus scattering (CE$ν$NS) from $^{8}$B solar neutrinos with the LUX-ZEPLIN experiment. This analysis uses a 5.7 tonne-year exposure with data collected between March 2023 and April 2025. In an energy range spanning 1-6 keV, we report no significant excess of events attributable to dark matter nuclear recoils, but we observe a significant signal from $^{8}$B CE$ν$NS interactions that is consistent with expectation. We set world-leading limits on spin-independent and spin-dependent-neutron DM-nucleon interactions for masses down to 5 GeV/$c^2$. In the no-dark-matter scenario, we observe a signal consistent with $^{8}$B CE$ν$NS events, corresponding to a $4.5σ$ statistical significance. This is the most significant evidence of $^{8}$B CE$ν$NS interactions and is enabled by robust background modeling and mitigation techniques. This demonstrates LZ's ability to detect rare signals at keV-scale energies.
High Energy Physics experiments like the LUX-ZEPLIN dark matter experiment face unique challenges when running their computation on High Performance Computing resources. In this paper, we describe some strategies to optimize memory usage of simulation codes with the help of profiling tools. We employed this approach and achieved memory reduction of 10-30\%. While this has been performed in the context of the LZ experiment, it has wider applicability to other HEP experimental codes that face these challenges on modern computer architectures.
Elastic neutrino-electron scattering represents a powerful tool to investigate key neutrino properties. In view of the recent results released by the LUX-ZEPLIN collaboration, we provide a first determination of the limits achievable on the neutrino magnetic moment and neutrino millicharge, whose effect becomes non-negligible in some beyond the Standard Model theories. In this context, we evaluate and discuss the impact of different approximations to describe the neutrino interaction with atomic electrons. The new LUX-ZEPLIN data allows us to set a very competitive limit on the neutrino magnet…
Interpreting the High-Recoil LUX-ZEPLIN Event with Bino-/Singlino-like and Higgsino Dark Matter
Argonne National Laboratory（阿贡国家实验室）；University of Cincinnati（辛辛那提大学）；Johannes Gutenberg University（约翰内斯·古腾堡大学）；University of Chicago（芝加哥大学）；Perimeter Institute for Theoretical Physics（理论物理珀米特研究所）
Inelastic Self-interacting Dark Matter and LUX-ZEPLIN 248 keV Event in a Dirac Modular Inverse Seesaw
Salbari College（萨尔巴里学院）；University of Silesia（西里西亚大学）；Indian Institute of Technology Goa（印度理工学院果阿分校）；Indian Institute of Technology Hyderabad（印度理工学院海德拉巴分校）
A scalar-extended ${\rm U(1)_{L_μ-L_τ}}$ explanation of the LUX-ZEPLIN 248 keV excess
Institute of Physics（印度物理研究所）；Homi Bhabha National Institute, BARC Training School Complex（霍米·巴巴国立学院，BARC培训学院）；Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3（法国格勒诺布尔阿尔卑斯大学亚原子物理与宇宙学实验室）
Kaluza--Klein Dark-Photon Mediation of Inelastic Dark Matter at LUX-ZEPLIN
Center for Fundamental Physics, School of Artificial Intelligence, Hubei Polytechnic University（湖北理工学院人工智能学院基础物理中心）；Physics Department, Theory Division, University of Ioannina（伊奥尼纳大学理论部物理系）
Precision measurement of positron decay modes of Xe-125 in the LUX-ZEPLIN experiment
SLAC National Accelerator Laboratory（SLAC国家加速器实验室）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理与宇宙学研究所）；University College London (UCL)（伦敦大学学院）；Brown University（布朗大学）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；University of Zurich（苏黎世大学）；Imperial College London（帝国理工学院）；STFC Rutherford Appleton Laboratory (RAL)（STC鲁瑟福阿普尔顿实验室）；University of Maryland（马里兰大学）
Measurement of the Muon Flux at the Sanford Underground Research Facility with the LUX-ZEPLIN Dark Matter Detector
SLAC National Accelerator Laboratory（SLAC国家加速器实验室）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理与宇宙学研究所）；University College London（伦敦大学学院）；Brown University（布朗大学）；University of California, Santa Barbara（加利福尼亚大学圣巴巴拉分校）；University of Zurich（苏黎世大学）；Imperial College London（帝国理工学院）；STFC Rutherford Appleton Laboratory（STFC卢瑟福·阿普尔顿实验室）；University of Maryland（马里兰大学）
The LUX-ZEPLIN dark matter search aims to achieve a sensitivity to the WIMP-nucleon spin-independent cross-section down to (1--2)$\times10^{-12}$\,pb at a WIMP mass of 40 GeV/$c^2$. This paper describes the simulations framework that, along with radioactivity measurements, was used to support this projection, and also to provide mock data for validating reconstruction and analysis software. Of particular note are the event generators, which allow us to model the background radiation, and the detector response physics used in the production of raw signals, which can be converted into digitized …
Search for dark matter particle interactions in an extended nuclear recoil energy window with the LUX-ZEPLIN (LZ) experiment
SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理与宇宙学研究所）；University College London (UCL)（伦敦大学学院）；Brown University（布朗大学）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Lawrence Berkeley National Laboratory (LBNL)（劳伦斯伯克利国家实验室）；University of Zurich（苏黎世大学）；Imperial College London（帝国理工学院）；STFC Rutherford Appleton Laboratory (RAL)（英国科学与技术设施委员会卢瑟福阿普尔顿实验室）；University of Maryland（马里兰大学）；King’s College London（伦敦国王学院）
Study of few-electron backgrounds in the LUX-ZEPLIN detector
SLAC National Accelerator Laboratory（斯坦福直线加速器中心）；Kavli Institute for Particle Astrophysics and Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理与宇宙学研究所）；University College London (UCL)（伦敦大学学院）；Brown University（布朗大学）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；Imperial College London（帝国理工学院）；STFC Rutherford Appleton Laboratory (RAL)（英国科学与技术设施委员会卢瑟福阿普尔顿实验室）；University of Maryland（马里兰大学）
LUX-ZEPLIN (LZ) is a dark matter detector expected to obtain world-leading sensitivity to weakly interacting massive particles (WIMPs) interacting via nuclear recoils with a ~7-tonne xenon target mass. This manuscript presents sensitivity projections to several low-energy signals of the complementary electron recoil signal type: 1) an effective neutrino magnetic moment and 2) an effective neutrino millicharge, both for pp-chain solar neutrinos, 3) an axion flux generated by the Sun, 4) axion-like particles forming the galactic dark matter, 5) hidden photons, 6) mirror dark matter, and 7) lepto…
The design and performance of the LUX-ZEPLIN (LZ) detector is described as of March 2015 in this Conceptual Design Report. LZ is a second-generation dark-matter detector with the potential for unprecedented sensitivity to weakly interacting massive particles (WIMPs) of masses from a few GeV/c2 to hundreds of TeV/c2. With total liquid xenon mass of about 10 tonnes, LZ will be the most sensitive experiment for WIMPs in this mass region by the end of the decade. This report describes in detail the design of the LZ technical systems. Expected backgrounds are quantified and the performance of the e…
LUX-ZEPLIN (LZ) is a next generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using a two-phase xenon detector with an active mass of 7~tonnes, LZ will search primarily for low-energy interactions with Weakly Interacting Massive Particles (WIMPs), which are hypothesized to make up the dark matter in our galactic halo. In this paper, the projected WIMP sensitivity of LZ is presented based on the latest background estimates and simulations of the detector. For a 1000~live day ru…
The nature of dark matter (DM) remains a mystery since it has so far eluded detection in the laboratory. To that end, the Large Underground Xenon (LUX) experiment was built to directly observe the interaction of DM with xenon target nuclei. LUX acquired data from April 2013 to May 2016 at SURF in South Dakota, which led to publications of many world-leading exclusion limits that probe much of the unexplored DM parameter space. This manuscript describes two novel direct detection methods that used the first LUX dataset to place limits on sub-GeV DM. The Bremsstrahlung and Migdal effects conside…
Isospin-violating dark matter (IVDM) has been proposed as a viable scenario to reconcile conflicting positive and null results from direct detection dark matter experiments. We show that the lowest-order dark matter-nucleus scattering rate can receive large and nucleus-dependent corrections at next-to-leading order (NLO) in the chiral expansion. The size of these corrections depends on the specific couplings of dark matter to quark flavors and gluons. In general the full NLO dark-matter-nucleus cross-section is not adequately described by just the zero-energy proton and neutron couplings. Thes…
We estimate the amount of $^{37}$Ar produced in natural xenon via cosmic ray-induced spallation, an inevitable consequence of the transportation and storage of xenon on the Earth's surface. We then calculate the resulting $^{37}$Ar concentration in a 10-tonne payload~(similar to that of the LUX-ZEPLIN experiment) assuming a representative schedule of xenon purification, storage and delivery to the underground facility. Using the spallation model by Silberberg and Tsao, the sea level production rate of $^{37}$Ar in natural xenon is estimated to be 0.024~atoms/kg/day. Assuming the xenon is succe…
Dark matter (DM) direct detections are investigated for models with the following properties: isospin-violating couplings, exothermic scatterings, and/or a light mediator, with the aim to reduce the tension between the CDMS-Si positive signals and other negative searches. In particular, we focus on the non-standard effective operators which could lead to the spin-independent DM-nucleus scatterings with non-trivial dependences on the transfer momentum or DM velocity. As a result, such effective operator choices have the very mild effects on the final fittings. Furthermore, by including the late…
In this Technical Design Report (TDR) we describe the LZ detector to be built at the Sanford Underground Research Facility (SURF). The LZ dark matter experiment is designed to achieve sensitivity to a WIMP-nucleon spin-independent cross section of three times ten to the negative forty-eighth square centimeters.
We describe the design and assembly of the LUX-ZEPLIN experiment, a direct detection search for cosmic WIMP dark matter particles. The centerpiece of the experiment is a large liquid xenon time projection chamber sensitive to low energy nuclear recoils. Rejection of backgrounds is enhanced by a Xe skin veto detector and by a liquid scintillator Outer Detector loaded with gadolinium for efficient neutron capture and tagging. LZ is located in the Davis Cavern at the 4850' level of the Sanford Underground Research Facility in Lead, South Dakota, USA. We describe the major subsystems of the experi…
LUX-ZEPLIN (LZ) is a second-generation direct dark matter experiment with spin-independent WIMP-nucleon scattering sensitivity above $1.4 \times 10^{-48}$ cm$^{2}$ for a WIMP mass of 40 GeV/c$^{2}$ and a 1000 d exposure. LZ achieves this sensitivity through a combination of a large 5.6 t fiducial volume, active inner and outer veto systems, and radio-pure construction using materials with inherently low radioactivity content. The LZ collaboration performed an extensive radioassay campaign over a period of six years to inform material selection for construction and provide an input to the exper…
We study a simplified model of top-flavoured dark matter in the framework of Dark Minimal Flavour Violation. In this setup the coupling of the dark matter flavour triplet to right-handed up-type quarks constitutes the only new source of flavour and CP violation. The parameter space of the model is restricted by LHC searches with missing energy final states, by neutral $D$ meson mixing data, by the observed dark matter relic abundance, and by the absence of signal in direct detection experiments. We consider all of these constraints in turn, studying their implications for the allowed parameter…
We present an experimental study of single electron emission in ZEPLIN-III, a two-phase xenon experiment built to search for dark matter WIMPs, and discuss applications enabled by the excellent signal-to-noise ratio achieved in detecting this signature. Firstly, we demonstrate a practical method for precise measurement of the free electron lifetime in liquid xenon during normal operation of these detectors. Then, using a realistic detector response model and backgrounds, we assess the feasibility of deploying such an instrument for measuring coherent neutrino-nucleus elastic scattering using t…
Inelastic Dark Matter and High-Energy Recoil Signatures in LZ
Department of Physics, Tsinghua University（清华大学物理系）；Center for High Energy Physics, Peking University（北京大学高能物理中心）；Department of Physics and Jockey Club Institute for Advanced Study, The Hong Kong University of Science and Technology（香港科技大学物理系及赛马会高等研究院）
Testing light and heavy vector mediators with solar CE$ν$NS measurements
Instituto de Física Corpuscular (IFIC), CSIC‐Universitat de Valéncia（粒子物理研究所（IFIC），西班牙科学委员会-瓦伦西亚大学）；University of Hamburg（汉堡大学）；Istituto Nazionale di Fisica Nucleare (INFN), Laboratori Nazionali del Gran Sasso（意大利国家核物理研究所（INFN），格兰萨索国家实验室）；Universidad Nacional Autónoma de México（墨西哥国立自治大学）；Gran Sasso Science Institute（格兰萨索科学研究所）
We describe a likelihood analysis using MasterCode of variants of the MSSM in which the soft supersymmetry-breaking parameters are assumed to have universal values at some scale $M_{in}$ below the supersymmetric grand unification scale $M_{GUT}$, as can occur in mirage mediation and other models. In addition to $M_{in}$, such `sub-GUT' models have the 4 parameters of the CMSSM, namely a common gaugino mass $m_{1/2}$, a common soft supersymmetry-breaking scalar mass $m_0$, a common trilinear mixing parameter $A$ and the ratio of MSSM Higgs vevs $\tanβ$, assuming that the Higgs mixing parameter …
Inelastic Singlet-Doublet Fermion Dark Matter in light of the 248 keV LZ event
Indian Institute of Technology Guwahati（印度理工学院古瓦哈提分校）；Indian Institute of Technology Hyderabad（印度理工学院海德拉巴分校）；Institute of Mathematical Sciences（数学科学研究所）
