Based on a sample of $2.7\times10^{9}$ $\psi(3686)$ events collected by the BESIII detector operating at the BEPCII collider, the decay $\psi(3686)\to\gamma\chi_{cJ}, \chi_{cJ}\to\eta\eta\eta^{\prime}$ is analyzed. The decay modes $\chi_{c1}$ and $\chi_{c2}\to\eta\eta\eta^{\prime}$ are observed for the first time, and their corresponding branching fractions are determined to be ${\cal{B}}(\chi_{c1}\to\eta\eta\eta^{\prime}) = $ $ (1.40\, \pm 0.13\, (\text{stat.}) \pm 0.09\, (\text{sys.})) \times 10^{-4}$ and ${\cal{B}}(\chi_{c2}\to\eta\eta\eta^{\prime}) = (4.18\, \pm 0.84\, (\text{stat.}) \pm 0.48\, (\text{sys.})) \times 10^{-5}$ . An upper limit on the branching fraction of $\chi_{c0}\to\eta\eta\eta^{\prime}$ is set as $2.59 \times 10^{-5}$ at a 90% confidence level (CL). A partial wave analysis (PWA) of the decay $\chi_{c1}\to\eta\eta\eta^{\prime}$ is performed to search for the $1^{-+}$ exotic state $\eta_1(1855)$ . The PWA result indicates that the structure in the $\eta\eta^{\prime}$ mass spectrum is attributed to $f_0(1500)$ , while in the $\eta\eta$ mass spectrum, it is attributed to the $0^{++}$ phase space. The upper limit of ${\cal{B}}(\chi_{c1}\to\eta_{1}(1855)\eta) \cdot {\cal{B}}(\eta_{1}(1855)\to\eta\eta^{\prime}) \lt $ $ 9.79 \times 10^{-5}$ is set based on the PWA at 90% CL.

China

M. Ablikim

Russia

M.N. Achasov

Sweden

P. Adlarson

X.C. Ai

Germany

R. Aliberti

Italy

A. Amoroso

Q. An

Y. Bai

O. Bakina

Y. Ban

H.R. Bao

Poland

V. Batozskaya

Mongolia

K. Begzsuren

N. Berger

M. Berlowski

M. Bertani

D. Bettoni

F. Bianchi

E. Bianco

A. Bortone

I. Boyko

United States

R.A. Briere

A. Brueggemann

H. Cai

M.H. Cai

X. Cai

A. Calcaterra

G.F. Cao

N. Cao

Türkiye

S.A. Cetin

X.Y. Chai

J.F. Chang

G.R. Che

Y.Z. Che

C.H. Chen

Chao Chen

G. Chen

H.S. Chen

H.Y. Chen

M.L. Chen

S.J. Chen

S.L. Chen

S.M. Chen

T. Chen

X.R. Chen

X.T. Chen

X.Y. Chen

Y.B. Chen

Y.Q. Chen

Z. Chen

Z.J. Chen

Z.K. Chen

S.K. Choi

X. Chu

G. Cibinetto

F. Cossio

United Kingdom

J. Cottee-Meldrum

J.J. Cui

H.L. Dai

J.P. Dai

A. Dbeyssi

R.E. de Boer

D. Dedovich

C.Q. Deng

Z.Y. Deng

A. Denig

I. Denysenko

M. Destefanis

F. De Mori

B. Ding

X.X. Ding

Y. Ding

Y.X. Ding

J. Dong

L.Y. Dong

M.Y. Dong

X. Dong

M.C. Du

S.X. Du

Y.Y. Duan

P. Egorov

G.F. Fan

J.J. Fan

Y.H. Fan

J. Fang

S.S. Fang

W.X. Fang

Y.Q. Fang

R. Farinelli

L. Fava

F. Feldbauer

G. Felici

C.Q. Feng

J.H. Feng

L. Feng

Q.X. Feng

Search for $\textit{η}$ $_{1}$(1855) in $\textit{χ}$ $\textit{cJ}$ → $\textit{ηηη}$′ decays * Supported in part by National Key R&D Program of China (2023YFA1606000, 2023YFA1606704); National Natural Science Foundation of China (NSFC) (11635010, 11935015, 11935016, 11935018, 12025502, 12035009, 12035013, 12061131003, 12192260, 12192261, 12192262, 12192263, 12192264, 12192265, 12221005, 12225509, 12235017, 12361141819); the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; CAS (YSBR-101); 100 Talents Program of CAS; The Institute of Nuclear and Particle Physics (INPAC) and Shanghai Key Laboratory for Particle Physics and Cosmology; Agencia Nacional de Investigación y Desarrollo de Chile (ANID), Chile (ANID PIA/APOYO AFB230003); German Research Foundation DFG (FOR5327); Istituto Nazionale di Fisica Nucleare, Italy; Knut and Alice Wallenberg Foundation (2021.0174, 2021.0299); Ministry of Development of Turkey (DPT2006K-120470); National Research Foundation of Korea ( NRF-2022R1A2C1092335); National Science and Technology fund of Mongolia; National Science Research and Innovation Fund (NSRF) via the Program Management Unit for Human Resources Institutional Development, Research and Innovation of Thailand ( B50G670107); Polish National Science Centre (2024/53/B/ST2/00975); Swedish Research Council (2019.04595); U. S. Department of Energy (DE-FG02-05ER41374)

Based on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> annihilation data collected with the BESIII detector at the BEPCII collider, searches for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msub><mi mathvariant="normal">Σ</mi><mi>c</mi></msub><msub><mover accent="true"><mi mathvariant="normal">Σ</mi><mo stretchy="false">¯</mo></mover><mi>c</mi></msub></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi mathvariant="normal">Σ</mi><mi>c</mi><mo>+</mo></msubsup><msubsup><mover accent="true"><mi mathvariant="normal">Σ</mi><mo stretchy="false">¯</mo></mover><mi>c</mi><mo>−</mo></msubsup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mn>0</mn></mrow></msubsup><msubsup><mrow><mover accent="true"><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mi>c</mi></mrow><mrow><mn>0</mn></mrow></msubsup></mrow></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo><mo>+</mo></mrow></msubsup><msubsup><mrow><mover accent="true"><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mi>c</mi></mrow><mrow><mo>−</mo><mo>−</mo></mrow></msubsup></mrow></math>) processes, as well as for the process <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msubsup><mi mathvariant="normal">Λ</mi><mi>c</mi><mo>+</mo></msubsup><msubsup><mover accent="true"><mi mathvariant="normal">Σ</mi><mo stretchy="false">¯</mo></mover><mi>c</mi><mo>−</mo></msubsup></math>, are conducted for the first time at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>4.750</mn></math>, 4.781, 4.843, 4.918, and 4.951 GeV. As no signals are observed for all the above channels, the upper limits on their Born cross sections at the 90% confidence level are reported. The obtained upper limits of cross sections for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msub><mi mathvariant="normal">Σ</mi><mi>c</mi></msub><msub><mover accent="true"><mi mathvariant="normal">Σ</mi><mo stretchy="false">¯</mo></mover><mi>c</mi></msub></math> are more than 2 orders of magnitude smaller than those for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msubsup><mi mathvariant="normal">Λ</mi><mi>c</mi><mo>+</mo></msubsup><msubsup><mover accent="true"><mi mathvariant="normal">Λ</mi><mo stretchy="false">¯</mo></mover><mi>c</mi><mo>−</mo></msubsup></math> near the threshold. In contrast, such suppression is absent in hyperon pair production (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><mi mathvariant="normal">Λ</mi><mover accent="true"><mi mathvariant="normal">Λ</mi><mo stretchy="false">¯</mo></mover></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">Σ</mi><mover accent="true"><mi mathvariant="normal">Σ</mi><mo stretchy="false">¯</mo></mover></math>), suggesting distinct underlying dynamics in charmed baryon production.

JINR

G. Chelkov

South Korea

Z.H. Duan

Measurements of the cross sections of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup><mo stretchy="false">→</mo><msub><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mi>c</mi></mrow></msub><msub><mrow><mover accent="true"><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mi>c</mi></mrow></msub></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi mathvariant="normal">Λ</mi></mrow><mrow><mi>c</mi></mrow><mrow><mo>+</mo></mrow></msubsup><msubsup><mrow><mover accent="true"><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mi>c</mi></mrow><mrow><mo>−</mo></mrow></msubsup></mrow></math> near kinematic thresholds

Based on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>12.0</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math> of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> collision data samples collected by the BESIII detector at center-of-mass energies from 4.1271 to 4.3583 GeV, a partial wave analysis is performed for the process <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><mi>J</mi><mo>/</mo><mi>ψ</mi></math>. The cross sections for the subprocesses <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msub><mi>Z</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>3900</mn><msup><mo stretchy="false">)</mo><mo>−</mo></msup><mo>+</mo><mi mathvariant="normal">c</mi><mo>.</mo><mi mathvariant="normal">c</mi><mo>.</mo><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><mi>J</mi><mo>/</mo><mi>ψ</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>f</mi><mn>0</mn></msub><mo stretchy="false">(</mo><mn>980</mn><mo stretchy="false">)</mo><mo stretchy="false">(</mo><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><mo stretchy="false">)</mo><mi>J</mi><mo>/</mo><mi>ψ</mi></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">(</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><msub><mo stretchy="false">)</mo><mrow><mi mathvariant="normal">S</mi><mtext>−</mtext><mrow><mi>wave</mi></mrow></mrow></msub><mi>J</mi><mo>/</mo><mi>ψ</mi></math> are measured for the first time. The mass and width of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>Z</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>3900</mn><msup><mo stretchy="false">)</mo><mo>±</mo></msup></math> are determined to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3884.6</mn><mo>±</mo><mn>0.7</mn><mo>±</mo><mn>3.3</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi><mo>/</mo><msup><mi>c</mi><mn>2</mn></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>37.2</mn><mo>±</mo><mn>1.3</mn><mo>±</mo><mn>6.6</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>, respectively. The first errors are statistical and the second systematic. The final state <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">(</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><msub><mo stretchy="false">)</mo><mrow><mi mathvariant="normal">S</mi><mtext>−</mtext><mrow><mi>wave</mi></mrow></mrow></msub><mi>J</mi><mo>/</mo><mi>ψ</mi></math> dominates the process <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><mi>J</mi><mo>/</mo><mi>ψ</mi></math>. By analyzing the cross sections of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>π</mi><mo>±</mo></msup><msub><mi>Z</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>3900</mn><msup><mo stretchy="false">)</mo><mo>∓</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>f</mi><mn>0</mn></msub><mo stretchy="false">(</mo><mn>980</mn><mo stretchy="false">)</mo><mi>J</mi><mo>/</mo><mi>ψ</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>4220</mn><mo stretchy="false">)</mo></math> has been observed. Its mass and width are determined to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4225.7</mn><mo>±</mo><mn>4.1</mn><mo>±</mo><mn>3.4</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi><mo>/</mo><msup><mi>c</mi><mn>2</mn></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>57.5</mn><mo>±</mo><mn>9.4</mn><mo>±</mo><mn>12.1</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>, respectively.

O. Afedulidis

I. Balossino

C. Chen

Z.Y. Chen

Y. Fang

Y.T. Feng

M. Fritsch

C.D. Fu

J.L. Fu

Y.W. Fu

H. Gao

X.B. Gao

Y.N. Gao

Partial wave analysis of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><mi>J</mi><mo>/</mo><mi>ψ</mi></math> and cross section measurement of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><msup><mi>π</mi><mo>±</mo></msup><msub><mi>Z</mi><mi>c</mi></msub><mo stretchy="false">(</mo><mn>3900</mn><msup><mo stretchy="false">)</mo><mo>∓</mo></msup></math> from 4.1271 to 4.3583 GeV

Supernova shocks can boost dark matter (DM) particles to high, yet nonrelativistic, velocities, providing a suitable mechanism for analysis within the framework of the nonrelativistic effective field theory (NREFT). These accelerated DM sources extend the experimental ability to scan the parameter space of light DM into the sub-GeV region. In this study, we specifically analyze DM accelerated by the Monogem Ring supernova remnant, whose age (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>∼</mo><mn>68000</mn><mtext> </mtext><mtext> </mtext><mi>yr</mi></math>) and distance to Earth (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>∼</mo><mn>300</mn></math> parsec) are strategically matched to enable detection with current terrestrial detectors. Utilizing the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>205.4</mn><mtext> </mtext><mtext> </mtext><mi>kg</mi><mo>·</mo><mi>day</mi></mrow></math> data obtained from the CDEX-10 experiment at the China Jinping Underground Laboratory, we derive new constraints on boosted DM within the NREFT framework. The NREFT coupling constant exclusion regions now penetrate the sub-GeV mass range, with optimal sensitivity achieved for operators <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi mathvariant="script">O</mi><mn>3</mn></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi mathvariant="script">O</mi><mn>6</mn></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi mathvariant="script">O</mi><mn>15</mn></msub></math> in the 0.4–0.6 GeV mass range.

J.Z. Wang

L.T. Yang

Q. Yue

K.J. Kang

Y.J. Li

H.P. An

Taiwan

Greeshma C.

J.P. Chang

H. Chen

Y.H. Chen

J.P. Cheng

W.H. Dai

Z. Deng

C.H. Fang

X.P. Geng

H. Gong

Q.J. Guo

T. Guo

X.Y. Guo

L. He

J.R. He

H.X. Huang

T.C. Huang

S. Karmakar

H.B. Li

H.Y. Li

J.M. Li

J. Li

M.C. Li

Q.Y. Li

R.M.J. Li

X.Q. Li

Y.L. Li

Y.F. Liang

B. Liao

F.K. Lin

S.T. Lin

J.X. Liu

R.Z. Liu

S.K. Liu

Y.D. Liu

Y. Liu

Y.Y. Liu

H. Ma

Y.C. Mao

A. Mureed

Q.Y. Nie

H. Pan

N.C. Qi

J. Ren

X.C. Ruan

M.B. Shen

H.Y. Shi

M.K. Singh

T.X. Sun

W.L. Sun

C.J. Tang

Y. Tian

H.F. Wan

G.F. Wang

L. Wang

Q. Wang

Y.F. Wang

Y.X. Wang

H.T. Wong

Y.C. Wu

H.Y. Xing

K.Z. Xiong

R. Xu

Y. Xu

Constraints on dark matter boosted by supernova shock within the effective field theory framework from the CDEX-10 experiment