The BESIII Collaboration has recently reported a new resonance structure in the cross-section analyses of 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><mi>ρ</mi><mi>π</mi></math> and <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>ρ</mi><mo stretchy="false">(</mo><mn>1450</mn><mo stretchy="false">)</mo><mi>π</mi></math> processes, displaying characteristics akin to an <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ω</mi></math> meson. However, its measured mass, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>M</mi><mo>=</mo><mn>2119</mn><mo>±</mo><mn>11</mn><mo>±</mo><mn>15</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>, significantly deviates from the predictions of the unquenched relativized potential model for conventional <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ω</mi></math> vector meson spectroscopy. To address this discrepancy, we propose a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><mi>S</mi><mo>−</mo><mn>3</mn><mi>D</mi></math> mixing scheme and investigate the corresponding decay properties within this framework. Our analysis demonstrates that the mixed state <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>ω</mi><mrow><mn>4</mn><mi>S</mi><mo>−</mo><mn>3</mn><mi>D</mi></mrow><mo>′</mo></msubsup></math> exhibits excellent agreement with the observed resonance, not only in mass and width but also in the products of its dielectron width and branching ratios, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi mathvariant="normal">Γ</mi></mrow><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow><mrow><mi mathvariant="script">R</mi></mrow></msubsup><mo>×</mo><msub><mrow><mi mathvariant="script">B</mi></mrow><mrow><mi mathvariant="script">R</mi><mo stretchy="false">→</mo><mi>ρ</mi><mi>π</mi></mrow></msub></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi mathvariant="normal">Γ</mi></mrow><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow><mrow><mi mathvariant="script">R</mi></mrow></msubsup><mo>×</mo><msub><mrow><mi mathvariant="script">B</mi></mrow><mrow><mi mathvariant="script">R</mi><mo stretchy="false">→</mo><mi>ρ</mi><mo stretchy="false">(</mo><mn>1450</mn><mo stretchy="false">)</mo><mi>π</mi><mo stretchy="false">→</mo><msup><mrow><mi>π</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mo>−</mo></mrow></msup><msup><mrow><mi>π</mi></mrow><mrow><mn>0</mn></mrow></msup></mrow></msub></mrow></math>. The determined mixing angle, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>θ</mi><mo>=</mo><mo>−</mo><mrow><mo stretchy="false">(</mo><msubsup><mrow><mn>31.1</mn></mrow><mrow><mo>−</mo><mn>3.1</mn></mrow><mrow><mo>+</mo><mn>2.1</mn></mrow></msubsup><mo stretchy="false">)</mo></mrow><mi>°</mi></mrow></math>, strongly supports the interpretation of this structure as the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>ω</mi><mrow><mn>4</mn><mi>S</mi><mo>−</mo><mn>3</mn><mi>D</mi></mrow><mo>′</mo></msubsup></math> state. Furthermore, we predict dominant decay channels for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>ω</mi><mrow><mn>4</mn><mi>S</mi><mo>−</mo><mn>3</mn><mi>D</mi></mrow><mo>′</mo></msubsup></math> and its partner state <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>ω</mi><mrow><mn>4</mn><mi>S</mi><mo>−</mo><mn>3</mn><mi>D</mi></mrow><mrow><mo>′′</mo></mrow></msubsup></math>. These predictions, together with the proposed mixing mechanism, provide crucial guidance for future experimental studies aimed at probing this structure and rigorously testing the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><mi>S</mi><mo>−</mo><mn>3</mn><mi>D</mi></math> mixing hypothesis.

China

Zi-Yue Bai

Qin-Song Zhou

Xiang Liu

Role of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><mi>S</mi><mo>−</mo><mn>3</mn><mi>D</mi></math> mixing in explaining the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ω</mi></math>-like <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>2119</mn><mo stretchy="false">)</mo></math> observed in <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>ρ</mi><mi>π</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ρ</mi><mo stretchy="false">(</mo><mn>1450</mn><mo stretchy="false">)</mo><mi>π</mi></math>

In this work a comprehensive analysis of the mass spectrum and decay properties of charmonium states within a relativistic framework is carried out. The present experimental status of charmonium states is reviewed. Utilizing a screened potential model, we compute the spectra and various decay widths for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>c</mi><mover accent="true"><mi>c</mi><mo stretchy="false">¯</mo></mover></math> bound system, comparing our results with experimental data and existing theoretical models. We calculate the decay constants, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>E</mi><mn>1</mn></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>M</mi><mn>1</mn></math> transitions, and annihilation decay widths, confirming the consistency of our model with experimental observations for well-established charmonium states. The interpretation of charmoniumlike states <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>4140</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>4274</mn><mo stretchy="false">)</mo></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>4500</mn><mo stretchy="false">)</mo></math> as <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>P</mi></math>-wave charmonium states and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ψ</mi><mo stretchy="false">(</mo><mn>4040</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ψ</mi><mo stretchy="false">(</mo><mn>3770</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ψ</mi><mo stretchy="false">(</mo><mn>4160</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ψ</mi><mo stretchy="false">(</mo><mn>4230</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ψ</mi><mo stretchy="false">(</mo><mn>4360</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ψ</mi><mo stretchy="false">(</mo><mn>4415</mn><mo stretchy="false">)</mo></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>4500</mn><mo stretchy="false">)</mo></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>4360</mn><mo stretchy="false">)</mo></math> as <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mo>−</mo><mi>D</mi></math> mixed charmonium states is carried out.

India

Chaitanya Anil Bokade

 Bhaghyesh

Conventional and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>X</mi><mi>Y</mi><mi>Z</mi></mrow></math> charmonium states in a relativistic screened potential model

In the present work, we investigate the production of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>4630</mn><mo stretchy="false">)</mo></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>4626</mn><mo stretchy="false">)</mo></math> in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>B</mi><mi>s</mi><mn>0</mn></msubsup></math> decays, where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>4630</mn><mo stretchy="false">)</mo></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>4626</mn><mo stretchy="false">)</mo></math> are considered as the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>C</mi></mrow></math>- parity pigeon pair in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>D</mi><mi>s</mi><mrow><mo>*</mo><mo>+</mo></mrow></msubsup><msub><mi>D</mi><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo stretchy="false">(</mo><mn>2536</mn><msup><mo stretchy="false">)</mo><mo>−</mo></msup></math> molecular frame. The branching fractions of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>K</mi><mo>+</mo></msup><mi>X</mi><mo stretchy="false">(</mo><mn>4630</mn><mo stretchy="false">)</mo><mo>/</mo><mi>Y</mi><mo stretchy="false">(</mo><mn>4626</mn><mo stretchy="false">)</mo></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>B</mi><mi>s</mi><mn>0</mn></msubsup><mo stretchy="false">→</mo><mi>η</mi><mi>X</mi><mo stretchy="false">(</mo><mn>4630</mn><mo stretchy="false">)</mo><mo>/</mo><mi>Y</mi><mo stretchy="false">(</mo><mn>4626</mn><mo stretchy="false">)</mo></math> have been evaluated using an effective Lagrangian approach, which are of the order of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>10</mn><mrow><mo>−</mo><mn>5</mn></mrow></msup></math> and the ratios of these branching fractions are almost independent on the model parameter. Based on the present estimations, we propose to search <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>4626</mn><mo stretchy="false">)</mo></math> in the process <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msup><mi>K</mi><mo>+</mo></msup><mi>J</mi><mo>/</mo><mi>ψ</mi><msup><mi>η</mi><mrow><mo stretchy="false">(</mo><mo>′</mo><mo stretchy="false">)</mo></mrow></msup></math>, which should be accessible by the LHCb and Belle II Collaborations.

Zhuo Yu

Qi Wu

Dian-Yong Chen

<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>4630</mn><mo stretchy="false">)</mo></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Y</mi><mo stretchy="false">(</mo><mn>4626</mn><mo stretchy="false">)</mo></math> production in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>B</mi><mi>s</mi><mn>0</mn></msubsup></math> decays

The Super-Kamiokande and T2K Collaborations present a joint measurement of neutrino oscillation parameters from their atmospheric and beam neutrino data. It uses a common interaction model for events overlapping in neutrino energy and correlated detector systematic uncertainties between the two datasets, which are found to be compatible. Using 3244.4 days of atmospheric data and a beam exposure of <math><mn>19.7</mn><mo>(</mo><mn>16.3</mn><mo>)</mo><mo>×</mo><msup><mn>10</mn><mn>20</mn></msup></math> protons on target in (anti)neutrino mode, the analysis finds a <math><mrow><mn>1.9</mn><mi>σ</mi></mrow></math> exclusion of <math><mi>C</mi><mi>P</mi></math> conservation (defined as <math><msub><mi>J</mi><mrow><mi>C</mi><mi>P</mi></mrow></msub><mo>=</mo><mn>0</mn></math>) and a <math><mrow><mn>1.2</mn><mi>σ</mi></mrow></math> exclusion of the inverted mass ordering.

Japan

K. Abe

S. Abe

C. Bronner

Y. Hayato

K. Hiraide

K. Hosokawa

K. Ieki

M. Ikeda

J. Kameda

Y. Kanemura

R. Kaneshima

Y. Kashiwagi

Y. Kataoka

S. Miki

United States

S. Mine

M. Miura

S. Moriyama

M. Nakahata

Y. Nakano

S. Nakayama

Y. Noguchi

K. Sato

H. Sekiya

H. Shiba

K. Shimizu

M. Shiozawa

Y. Sonoda

Y. Suzuki

A. Takeda

Y. Takemoto

H. Tanaka

T. Yano

S. Han

T. Kajita

K. Okumura

T. Tashiro

T. Tomiya

X. Wang

S. Yoshida

Spain

P. Fernandez

L. Labarga

N. Ospina

B. Zaldivar

Canada

B. W. Pointon

E. Kearns

J. Mirabito

J. L. Raaf

L. Wan

T. Wester

J. Bian

N. J. Griskevich

M. B. Smy

H. W. Sobel

V. Takhistov

A. Yankelevich

J. Hill

South Korea

M. C. Jang

S. H. Lee

D. H. Moon

R. G. Park

B. Bodur

K. Scholberg

C. W. Walter

France

A. Beauchêne

O. Drapier

A. Giampaolo

Th. A. Mueller

A. D. Santos

P. Paganini

B. Quilain

R. Rogly

T. Nakamura

J. S. Jang

United Kingdom

L. N. Machado

J. G. Learned

K. Choi

N. Iovine

Vietnam

S. Cao

L. H. V. Anthony

D. Martin

N. W. Prouse

M. Scott

Y. Uchida

Italy

V. Berardi

N. F. Calabria

M. G. Catanesi

E. Radicioni

A. Langella

G. De Rosa

G. Collazuol

M. Feltre

F. Iacob

M. Mattiazzi

L. Ludovici

M. Gonin

L. Périssé

G. Pronost

C. Fujisawa

S. Horiuchi

M. Kobayashi

First Joint Oscillation Analysis of Super-Kamiokande Atmospheric and T2K Accelerator Neutrino Data

A search for proton decay into <math><msup><mi>e</mi><mo>+</mo></msup><mo>/</mo><msup><mi>μ</mi><mo>+</mo></msup></math> and a <math><mi>η</mi></math> meson has been performed using data from a <math><mrow><mn>0.373</mn><mtext> </mtext><mtext> </mtext><mi>Mton</mi><mo>·</mo><mi>year</mi></mrow></math> exposure (6050.3 live days) of Super-Kamiokande. Compared to previous searches this work introduces an improved model of the intranuclear <math><mi>η</mi></math> interaction cross section, resulting in a factor of 2 reduction in uncertainties from this source and <math><mo>∼</mo><mn>10</mn><mo>%</mo></math> increase in signal efficiency. No significant data excess was found above the expected number of atmospheric neutrino background events resulting in no indication of proton decay into either mode. Lower limits on the proton partial lifetime of <math><mrow><mn>1.4</mn><mo>×</mo><msup><mn>10</mn><mn>34</mn></msup><mtext> </mtext><mtext> </mtext><mi>years</mi></mrow></math> for <math><mi>p</mi><mo>→</mo><msup><mi>e</mi><mo>+</mo></msup><mi>η</mi></math> and <math><mrow><mn>7.3</mn><mo>×</mo><msup><mn>10</mn><mn>33</mn></msup><mtext> </mtext><mtext> </mtext><mi>years</mi></mrow></math> for <math><mi>p</mi><mo>→</mo><msup><mi>μ</mi><mo>+</mo></msup><mi>η</mi></math> at the 90% CL were set. These limits are around 1.5 times longer than our previous study and are the most stringent to date.

N. Taniuchi

Y. Asaoka

M. Harada

K. Okamoto

A. Takenaka

S. Watanabe

G. D. Megias

W. R. Kropp

S. Locke

J. Y. Kim

I. T. Lim

B. S. Yang

L. Bernard

A. Coffani

S. El Hedri

A. A. Sztuc

Search for proton decay via <math><mi>p</mi><mo>→</mo><mrow><msup><mi>e</mi><mo>+</mo></msup><mi>η</mi></mrow></math> and <math><mi>p</mi><mo>→</mo><mrow><msup><mi>μ</mi><mo>+</mo></msup><mi>η</mi></mrow></math> with a 0.37 Mton-year exposure of Super-Kamiokande

We present the results of the charge ratio (<math><mi>R</mi></math>) and polarization (<math><msubsup><mi>P</mi><mn>0</mn><mi>μ</mi></msubsup></math>) measurements using decay electron events collected between September 2008 and June 2022 with the Super-Kamiokande detector. Because of its underground location and long operation, we are able to perform high-precision measurements by accumulating cosmic-ray muons. We measured the muon charge ratio to be <math><mi>R</mi><mo>=</mo><mn>1.32</mn><mo>±</mo><mn>0.02</mn><mo>(</mo><mrow><mi>stat</mi></mrow><mo>+</mo><mrow><mi>syst</mi></mrow><mo>)</mo></math> at <math><msub><mi>E</mi><mi>μ</mi></msub><mi>cos</mi><msub><mi>θ</mi><mtext>Zenith</mtext></msub><mo>=</mo><msubsup><mn>0.7</mn><mrow><mo>−</mo><mn>0.2</mn></mrow><mrow><mo>+</mo><mn>0.3</mn></mrow></msubsup><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>, where <math><msub><mi>E</mi><mi>μ</mi></msub></math> is the muon energy and <math><msub><mi>θ</mi><mtext>Zenith</mtext></msub></math> is the zenith angle of incoming cosmic-ray muons. This result is consistent with the Honda flux model while indicating a tension with the <math><mi>π</mi><mi>K</mi></math> model of <math><mn>1.9</mn><mi>σ</mi></math>. We also measured the muon polarization at the production location to be <math><mrow><msubsup><mrow><mi>P</mi></mrow><mrow><mn>0</mn></mrow><mrow><mi>μ</mi></mrow></msubsup><mo>=</mo><mn>0.52</mn><mo>±</mo><mn>0.02</mn><mtext> </mtext><mtext> </mtext><mo>(</mo><mrow><mi>stat</mi></mrow><mo>+</mo><mrow><mi>syst</mi></mrow><mo>)</mo></mrow></math> at the muon momentum of <math><msubsup><mn>0.9</mn><mrow><mo>−</mo><mn>0.1</mn></mrow><mrow><mo>+</mo><mn>0.6</mn></mrow></msubsup><mtext> </mtext><mtext> </mtext><mi>TeV</mi><mo>/</mo><mi>c</mi></math> at the surface of the mountain; this also suggests a tension with the Honda flux model of <math><mn>1.5</mn><mi>σ</mi></math>. This is the most precise measurement ever to experimentally determine the cosmic-ray muon polarization near <math><mn>1</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi><mo>/</mo><mi>c</mi></math>. These measurement results are useful to improve atmospheric neutrino simulations.

H. Kitagawa

T. Tada

G.D. Megias

J.L. Raaf

B.W. Pointon

N.J. Griskevich

M.B. Smy

H.W. Sobel

M.C. Jang

S.H. Lee

D.H. Moon

R.G. Park

C.W. Walter

Th. A. Mueller

A.D. Santos

J.S. Jang

L.N. Machado

J.G. Learned

L.H.V. Anthony

D. Marin

N.W. Prouse

A.A. Sztuc

N.F. Calabria

M.G. Catanesi

M. Lamoureux

Measurements of the charge ratio and polarization of cosmic-ray muons with the Super-Kamiokande detector

In this work, we investigate the hidden charm decays properties of <math><mrow><mi>Y</mi><mo>(</mo><mn>4626</mn><mo>)</mo></mrow></math>, where <math><mrow><mi>Y</mi><mo>(</mo><mn>4626</mn><mo>)</mo></mrow></math> is assigned as a <math><mrow><mi>S</mi><mo>−</mo></mrow></math>wave <math><mrow><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>*</mo><mo>+</mo></mrow></msubsup><msub><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo>(</mo><mn>2536</mn><msup><mrow><mo>)</mo></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> molecular state with <math><mrow><msup><mrow><mi>J</mi></mrow><mrow><mi>P</mi><mi>C</mi></mrow></msup><mo>=</mo><msup><mrow><mn>1</mn></mrow><mrow><mo>−</mo><mo>−</mo></mrow></msup></mrow></math>. The partial widths of the processes <math><mrow><mi>Y</mi><mo>(</mo><mn>4626</mn><mo>)</mo><mo>→</mo><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>η</mi></mrow></math>, <math><mrow><mi>J</mi><mo>/</mo><mi>ψ</mi><msup><mrow><mi>η</mi></mrow><mrow><mo>′</mo></mrow></msup></mrow></math>, <math><mrow><msub><mrow><mi>η</mi></mrow><mrow><mi>c</mi></mrow></msub><mi>ϕ</mi></mrow></math>, and <math><mrow><msub><mrow><mi>χ</mi></mrow><mrow><mi>c</mi><mi>J</mi></mrow></msub><mi>ϕ</mi><mo>,</mo><mo>(</mo><mi>J</mi><mo>=</mo><mo>{</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>}</mo><mo>)</mo></mrow></math> are estimated by employing the effective Lagrangian approach. The present estimations indicate that the partial widths of the <math><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>η</mi></math> and <math><mi>J</mi><mo>/</mo><mi>ψ</mi><msup><mi>η</mi><mo>′</mo></msup></math> channels are of the order of 1 MeV, while the one of <math><msub><mi>χ</mi><mrow><mi>c</mi><mn>1</mn></mrow></msub><mi>ϕ</mi></math> is of the order of 0.1 MeV. Thus, we propose to further examine the molecular interpretation of <math><mi>Y</mi><mo>(</mo><mn>4626</mn><mo>)</mo></math> by searching it in the cross sections for the <math><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo>→</mo><mi>J</mi><mo>/</mo><mi>ψ</mi><msup><mi>η</mi><mrow><mo>(</mo><mo>′</mo><mo>)</mo></mrow></msup></math> processes, which should be accessible by the BES III and Belle II.

Zi-Li Yue

Yue Pan

Hidden charm decays of <math><mrow><mi>Y</mi><mo>(</mo><mn>4626</mn><mo>)</mo></mrow></math> in a <math><mrow><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>*</mo><mo>+</mo></mrow></msubsup><msub><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo>(</mo><mn>2536</mn><msup><mrow><mo>)</mo></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> molecular frame

The two excited vector charmonium states <math><mi>Y</mi><mo>(</mo><mn>4220</mn><mo>)</mo></math> and <math><mi>Y</mi><mo>(</mo><mn>4360</mn><mo>)</mo></math> are difficult to understand as pure <math><mi>c</mi><mover><mi>c</mi><mo>¯</mo></mover></math> charmonium states. Since they are located close to the mass thresholds of <math><mover><mi>D</mi><mo>¯</mo></mover><msub><mi>D</mi><mn>1</mn></msub></math> and <math><msup><mover><mi>D</mi><mo>¯</mo></mover><mo>*</mo></msup><msub><mi>D</mi><mn>1</mn></msub></math>, they can be viewed as <math><mover><mi>D</mi><mo>¯</mo></mover><msub><mi>D</mi><mn>1</mn></msub></math> and <math><msup><mover><mi>D</mi><mo>¯</mo></mover><mo>*</mo></msup><msub><mi>D</mi><mn>1</mn></msub></math> molecules. Furthermore, recent studies indicate that the exotic states <math><mi>X</mi><mo>(</mo><mn>3872</mn><mo>)</mo><mo>/</mo><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>3900</mn><mo>)</mo></math> and <math><msub><mi>X</mi><mn>2</mn></msub><mo>(</mo><mn>4013</mn><mo>)</mo><mo>/</mo><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>4020</mn><mo>)</mo></math> are the isoscalar/isovector <math><mover><mi>D</mi><mo>¯</mo></mover><msup><mi>D</mi><mo>*</mo></msup></math> and isoscalar/isovector <math><msup><mover><mi>D</mi><mo>¯</mo></mover><mo>*</mo></msup><msup><mi>D</mi><mo>*</mo></msup></math> molecules, respectively. In this work, in the molecular picture, we employ the triangle diagram mechanism to study the productions of <math><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>3900</mn><mo>)</mo></math> and <math><mi>X</mi><mo>(</mo><mn>3872</mn><mo>)</mo></math> in the pionic and radiative decays of <math><mi>Y</mi><mo>(</mo><mn>4220</mn><mo>)</mo></math>, as well as their heavy-quark spin symmetry partners—i.e., the productions of <math><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>4020</mn><mo>)</mo></math> and <math><msub><mi>X</mi><mn>2</mn></msub><mo>(</mo><mn>4013</mn><mo>)</mo></math> in the pionic and radiative decays of <math><mi>Y</mi><mo>(</mo><mn>4360</mn><mo>)</mo></math>. Using the effective Lagrangian approach, we obtain the ratios of the branching fractions <math><mi>B</mi><mo>[</mo><mi>Y</mi><mo>(</mo><mn>4360</mn><mo>)</mo><mo>→</mo><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>4020</mn><mo>)</mo><mi>π</mi><mo>]</mo><mo>/</mo><mi>B</mi><mo>[</mo><mi>Y</mi><mo>(</mo><mn>4220</mn><mo>)</mo><mo>→</mo><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>3900</mn><mo>)</mo><mi>π</mi><mo>]</mo><mo>=</mo><mn>1.2</mn><mrow><mo>±</mo><mn>0.3</mn></mrow></math> and <math><mi>B</mi><mo>[</mo><mi>Y</mi><mo>(</mo><mn>4360</mn><mo>)</mo><mo>→</mo><msub><mi>X</mi><mn>2</mn></msub><mo>(</mo><mn>4013</mn><mo>)</mo><mi>γ</mi><mo>]</mo><mo>/</mo><mi>B</mi><mo>[</mo><mi>Y</mi><mo>(</mo><mn>4220</mn><mo>)</mo><mo>→</mo><mi>X</mi><mo>(</mo><mn>3872</mn><mo>)</mo><mi>γ</mi><mo>]</mo><mo>=</mo><mn>0.5</mn><mrow><mo>±</mo><mn>0.1</mn></mrow></math>, almost independent of model parameters, which indicate that the productions of <math><msub><mi>X</mi><mn>2</mn></msub><mo>(</mo><mn>4013</mn><mo>)</mo></math> and <math><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>4020</mn><mo>)</mo></math> in the radiative and pionic decays of <math><mi>Y</mi><mo>(</mo><mn>4360</mn><mo>)</mo></math> are likely to be measured in the future. The experimental studies of the predicted decay modes will help to verify the molecular nature of <math><mi>X</mi><mo>(</mo><mn>3872</mn><mo>)</mo></math>, <math><msub><mi>Z</mi><mi>c</mi></msub><mo>(</mo><mn>3900</mn><mo>)</mo></math>, and <math><mi>Y</mi><mo>(</mo><mn>4220</mn><mo>)</mo></math>. We hope that the present work can stimulate experimental and further theoretical studies on these decay modes.

Ming-Zhu Liu

Xi-Zhe Ling

Li-Sheng Geng

Productions of <math><mrow><mi>X</mi><mo>(</mo><mn>3872</mn><mo>)</mo><mo>/</mo><msub><mrow><mi>Z</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>(</mo><mn>3900</mn><mo>)</mo></mrow></math> and <math><mrow><msub><mrow><mi>X</mi></mrow><mn>2</mn></msub><mo>(</mo><mn>4013</mn><mo>)</mo><mo>/</mo><msub><mrow><mi>Z</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>(</mo><mn>4020</mn><mo>)</mo></mrow></math> in <math><mi>Y</mi><mo>(</mo><mn>4220</mn><mo>)</mo></math> and <math><mi>Y</mi><mo>(</mo><mn>4360</mn><mo>)</mo></math> decays

The Bell nonlocality and entanglement are two kinds of quantum correlations in quantum systems. Due to the recent upgrade in the Beijing Spectrometer III (BESIII) experiment, it is possible to explore the nonlocality and entanglement in hyperon-antihyperon systems produced in electron-positron annihilation with high precision data. We provide a systematic method for studying quantum correlations in spin-<math><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></math> hyperon-antihyperon systems through the measures for the nonlocality and entanglement. We find that with nonvanishing polarizations of the hyperon and its antihyperon, the kinematic region of nonlocality in the hyperon-antihyperon system is more restricted than the <math><msup><mi>τ</mi><mo>+</mo></msup><msup><mi>τ</mi><mo>−</mo></msup></math> system in which polarizations of <math><mi>τ</mi></math> leptons are vanishing. We also present an experimental proposal to probe the nonlocality and entanglement in hyperon-antihyperon systems at BSEIII.

Sihao Wu

Chen Qian

Qun Wang

Xiao-Rong Zhou

Bell nonlocality and entanglement in <math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup><mo>→</mo><mi>Y</mi><mover><mrow><mi>Y</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math> at BESIII

Radioactivity induced by cosmic muon spallation is a dominant source of backgrounds for <math><mrow><mi>O</mi><mo>(</mo><mn>10</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi><mo>)</mo></mrow></math> neutrino interactions in water Cherenkov detectors. In particular, it is crucial to reduce backgrounds to measure the solar neutrino spectrum and find neutrino interactions from distant supernovae. In this paper we introduce new techniques to locate muon-induced hadronic showers and efficiently reject spallation backgrounds. Applying these techniques to the solar neutrino analysis with an exposure of <math><mn>2790</mn><mo>×</mo><mn>22.5</mn><mtext> </mtext><mtext> </mtext><mi>kton</mi><mo>·</mo><mi>day</mi></math> increases the signal efficiency by 12.6%, approximately corresponding to an additional year of detector running. Furthermore, we present the first spallation simulation at Super-Kamiokande, where we model hadronic interactions using fluka. The agreement between the isotope yields and shower pattern in this simulation and in the data gives confidence in the accuracy of this simulation, and thus opens the door to use it to optimize muon spallation removal in new data with gadolinium-enhanced neutron capture detection.

S. Imaizumi

H. Ito

Y. Nagao

Y. Nakajima

T. Okada

A. Orii

K. Hirade

S. Watabe

J. Xia

D. Bravo-Berguño

Ll. Marti

F. d. M. Blaszczyk

J. L. Stone

New methods and simulations for cosmogenic induced spallation removal in Super-Kamiokande-IV