<p>We present searches for light dark matter (DM) with masses <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>3</mn><mi>–</mi><mn>9</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><msup><mrow><mi>c</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math> in the presence of coherent elastic neutrino-nucleus scattering (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>CE</mi><mi>ν</mi><mi>NS</mi></mrow></math>) from <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> solar neutrinos with the LUX-ZEPLIN experiment. This analysis uses a 5.7 tonne-yr 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 <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>CE</mi><mi>ν</mi><mi>NS</mi></mrow></math> 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 <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><msup><mi>c</mi><mn>2</mn></msup></math>. In the no-dark-matter scenario, we observe a signal consistent with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>CE</mi><mi>ν</mi><mi>NS</mi></mrow></math> events, corresponding to a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4.5</mn><mi>σ</mi></math> statistical significance. This is the most significant evidence of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>CE</mi><mi>ν</mi><mi>NS</mi></mrow></math> interactions and is enabled by robust background modeling and mitigation techniques. This demonstrates LZ’s ability to detect rare signals at keV-scale energies.</p>

United States

D.S. Akerib

United Kingdom

A.K. Al Musalhi

F. Alder

B.J. Almquist

C.S. Amarasinghe

A. Ames

T.J. Anderson

Switzerland

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

Portugal

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

Australia

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

South Korea

Y.D. Kim

D. Kodroff

E.V. Korolkova

H. Kraus

S. Kravitz

L. Kreczko

V.A. Kudryavtsev

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

<p>We report a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>3.3</mn><mi>σ</mi></mrow></math> measurement of coherent elastic neutrino-nucleus scattering from solar <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> neutrinos using a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>6.77</mn><mtext> </mtext><mtext> </mtext><mi mathvariant="normal">t</mi><mo>×</mo><mi>yr</mi></mrow></math> exposure from the XENONnT experiment, inferring a solar <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> neutrino flux of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo stretchy="false">(</mo><msubsup><mrow><mn>5</mn></mrow><mrow><mo>−</mo><mn>2</mn></mrow><mrow><mo>+</mo><mn>3</mn></mrow></msubsup><mo stretchy="false">)</mo><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>6</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>cm</mi></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup><mtext> </mtext><msup><mrow><mi mathvariant="normal">s</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math>, consistent with previous measurements. In the presence of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> “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 <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>5</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><msup><mrow><mi>c</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math> spin-independent weakly interacting massive particle by 10%. The dataset was also used to measure the weak mixing angle at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>∼</mo><mn>0.02</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><mi>c</mi></math> momentum transfer and constrain physics beyond the Standard Model.</p>

E. Aprile

Netherlands

J. Aalbers

Japan

K. Abe

Israel

M.M. Abu Rmeileh

M. Adrover

France

S. Ahmed Maouloud

Germany

L. Althueser

B. Andrieu

Italy

E. Angelino

D. Antón Martin

S.R. Armbruster

United Arab Emirates

F. Arneodo

L. Baudis

M. Bazyk

V. Beligotti

L. Bellagamba

R. Biondi

A. Bismark

K. Boese

R.M. Braun

G. Bruni

R. Budnik

China

C. Cai

C. Capelli

J.M.R. Cardoso

A.P. Cimental Chávez

A.P. Colijn

Sweden

J. Conrad

J.J. Cuenca-García

V. D’Andrea

L.C. Daniel Garcia

M.P. Decowski

A. Deisting

C. Di Donato

P. Di Gangi

S. Diglio

K. Eitel

S. el Morabit

R. Elleboro

A. Elykov

A.D. Ferella

C. Ferrari

H. Fischer

T. Flehmke

M. Flierman

R. Frankel

D. Fuchs

W. Fulgione

C. Fuselli

F. Gao

R. Giacomobono

F. Girard

R. Glade-Beucke

L. Grandi

J. Grigat

H. Guan

M. Guida

P. Gyorgy

R. Hammann

C. Hils

L. Hoetzsch

N.F. Hood

M. Iacovacci

Y. Itow

J. Jakob

F. Joerg

Y. Kaminaga

M. Kara

S. Kazama

P. Kharbanda

M. Kobayashi

D. Koke

K. Kooshkjalali

A. Kopec

E. Kozlova

H. Landsman

R.F. Lang

L. Levinson

A. Li

H. Li

I. Li

S. Li

S. Liang

Probing the Solar <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">B</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>8</mn></mrow></mmultiscripts></mrow></math> Neutrino Fog with XENONnT