The processes of $ K^-p \to \pi^0 \pi^0 \Sigma^0 $ and $ K^- p \to \pi^0 \Lambda(1405) $ are studied within the effective Lagrangian approach. In addition to the “background” contribution from the $\textit{u}$-channel nucleon pole term, the contribution from the $ \Sigma(1660) $ resonance with spin-parity $ J^P=1/2^+ $ is also considered. For the $ K^-p \to \pi^0 \pi^0 \Sigma^0 $ reaction, we perform a calculation for the total and differential cross sections by considering the contribution from the $ \Sigma(1660) $ intermediate resonance decaying into $ \pi^0 \Lambda(1405) $ with $ \Lambda(1405) $ decaying into $ \pi^0 \Sigma^0 $ . With our model parameters, the available experimental data on both the $ K^-p \to \pi^0 \pi^0 \Sigma^0 $ and $ K^- p \to \pi^0 \Lambda(1405) $ reactions can be fairly well reproduced. It is shown that the contribution from the $ \Sigma(1660) $ resonance is necessary, and that these experimental measurements could be used to determine some properties of the $ \Sigma(1660) $ resonance.

China

Xing-Yi Ji

Si-Wei Liu

Wen-Tao Lyu

De-Min Li

En Wang

Ju-Jun Xie

Role of Σ(1660) in the $\textit{K}$ $^{−}$ $\textit{p}$ → $\textit{π}$ $^{0}$ $\textit{π}$ $^{0}$Σ$^{0}$ reaction * Supported by the National Key R&D Program of China (2023YFA1606703, 2024YFE0105200), the National Natural Science Foundation of China (12435007, 12475086, 12192263, 12361141819, 1252200936), the Natural Science Foundation of Henan (232300421140, 252300423951) and the Zhengzhou University Young Student Basic Research Projects (PhD students) (ZDBJ202522)

<p>We report a search for an invisible particle <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math> in the decay <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi>K</mi></mrow><mrow><mi>L</mi></mrow><mrow><mn>0</mn></mrow></msubsup><mo stretchy="false">→</mo><mi>γ</mi><mi>X</mi></mrow></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">→</mo><mtext>invisible</mtext></math>), where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math> can be interpreted as a massless or massive dark photon. No evidence for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math> was found, based on 13 candidate events consistent with a predicted background of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>12.66</mn><mo>±</mo><mn>4.4</mn><msub><mrow><mn>2</mn></mrow><mrow><mi>stat</mi></mrow></msub><mo>±</mo><mn>2.1</mn><msub><mrow><mn>3</mn></mrow><mrow><mi>syst</mi></mrow></msub></mrow></math> events. Upper limits on the branching ratio of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>K</mi><mi>L</mi><mn>0</mn></msubsup><mo stretchy="false">→</mo><mi>γ</mi><mi>X</mi></math> were set for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math> mass range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>0</mn><mo>≤</mo><msub><mrow><mi>m</mi></mrow><mrow><mi>X</mi></mrow></msub><mo>≤</mo><mn>425</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi><mo>/</mo><msup><mrow><mi>c</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math>. For massless <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math>, the upper limit was <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3.4</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>7</mn></mrow></msup></math> at the 90% confidence level, improving the previous indirect bound by over three orders of magnitude. This result yielded a new lower bound of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4.1</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> on the probed effective mass scale governing flavor-changing dark-photon couplings, representing approximately two orders of magnitude improvement on existing constraints. For massive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi></math>, the upper limits in the searched mass region ranged from <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>7</mn></mrow></msup><mo stretchy="false">)</mo></math> to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup><mo stretchy="false">)</mo></math>.</p>

T. Wu

Taiwan

Y.C. Tung

Y.B. Hsiung

South Korea

J.K. Ahn

Japan

M. Gonzalez

E.J. Kim

T.K. Komatsubara

K. Kotera

S.K. Lee

G.Y. Lim

C. Lin

T. Matsumura

H. Nanjo

Y. Noichi

T. Nomura

T. Nunes

K. Ono

United States

J. Redeker

N. Shimizu

S. Shinohara

K. Shiomi

R. Shiraishi

Y. Tajima

Y.W. Wah

H. Watanabe

T. Yamanaka

H.Y. Yoshida

Search for Dark Particles in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi>K</mi></mrow><mrow><mi>L</mi></mrow><mrow><mn>0</mn></mrow></msubsup><mo stretchy="false">→</mo><mi>γ</mi><mi>X</mi></mrow></math> at the KOTO Experiment

Based on a sample of (10087 ± 44) × 10 $\textit{J}$/$\textit{ψ}$ events collected at the center-of-mass energy $$ \sqrt{s}=3.0969 $$ GeV with the BESIII detector, we search for the charmonium rare weak decay $$ J/\psi \to {\overline{D}}^0{\overline{K}}^{\ast 0}+\textrm{c}.\textrm{c}. $$ . No significant signal is observed, and the upper limit on its decay branching fraction at the 90% confidence level is set as 1.4 × 10 , improving the sensitivity of the previous best limit by an order of magnitude.

M. Ablikim

Russia

M. Achasov

Sweden

P. Adlarson

X. 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

R. Briere

A. Brueggemann

H. Cai

M. Cai

X. Cai

A. Calcaterra

G. Cao

N. Cao

Türkiye

S. Cetin

X. Chai

J. Chang

G. Che

Y. Che

C. Chen

Chao Chen

G. Chen

H. Chen

M. Chen

S. Chen

T. Chen

X. Chen

Y. Chen

Z. Chen

J. Cheng

S. Choi

X. Chu

G. Cibinetto

F. Cossio

United Kingdom

J. Cottee-Meldrum

J. Cui

H. Dai

J. Dai

X. Dai

A. Dbeyssi

R. Boer

D. Dedovich

C. Deng

Z. Deng

A. Denig

I. Denysenko

M. Destefanis

F. Mori

B. Ding

X. Ding

Y. Ding

J. Dong

L. Dong

M. Dong

X. Dong

M. Du

S. Du

Y. Duan

Z. Duan

P. Egorov

G. Fan

J. Fan

Y. Fan

J. Fang

S. Fang

W. Fang

Y. Fang

L. Fava

F. Feldbauer

G. Felici

C. Feng

J. Feng

L. Feng

Search for the charmonium weak decay $$ J/\psi \to {\overline{D}}^0{\overline{K}}^{\ast 0}+\textrm{c}.\textrm{c}. $$

Recent work on $\textit{B}$ → $\textit{π}$, $\textit{K}$ and $\textit{B}$ → $\textit{D}$ form factors from lattice QCD and light-cone sum rules has made it possible to constrain the inverse moment $\textit{λ}$ of the $\textit{B}$-meson light-cone distribution amplitudes by performing a global fit of $\textit{B}$ → $\textit{π}$, $\textit{K}$, $\textit{D}$ form factors. We have compiled the $\textit{B}$ → $\textit{π}$, $\textit{K}$, $\textit{D}$ form factors calculated by the HPQCD, MILC, and RBC/UKQCD collaborations in the large $\textit{q}$ region. By employing an three-parameter ansatz of the $\textit{B}$-meson light-cone distribution amplitudes, we express the $\textit{B}$ → $\textit{π}$, $\textit{K}$, $\textit{D}$ form factors at $\textit{q}$ = 0 that are calculated from light-cone sum rules, in terms of the inverse moment $\textit{λ}$ of the leading-twist $\textit{B}$-meson light-cone distribution amplitude. In the $\textit{B}$ → $\textit{πℓν}$ channel, we also include the available $\textit{q}$ -binned experimental data from the BaBar, Belle, and Belle II collaborations. Using the Bourrely-Caprini-Lellouch parametrization, we perform a global fit and obtain $\textit{λ}$ = $$ 217{(19)}_{-17}^{+82} $$ MeV and |$\textit{V}$ | = $$ 3.68{(13)}_{-1}^{+0} $$ × 10 . The second uncertainty is obtained by constraining $\textit{λ}$ > 200 MeV and varying the inverse logarithmic moments $$ {\hat{\sigma}}_1 $$ ∈ [−0.7, 0.7] and $$ {\hat{\sigma}}_2 $$ ∈ [−6, 6], which represents the model-dependent uncertainty from the $\textit{B}$-meson light-cone distribution amplitudes. When taking into account $\textit{λ}$ and $$ {\hat{\sigma}}_1 $$ as fitting parameters simultaneously, the intervals of our preditions are $\textit{λ}$ = [208, 324] MeV and $$ {\hat{\sigma}}_1 $$ = [−0.7, 0.27].

Dong-Hao Li

Cai-Dian Lü

Ulf-G. Meißner

Jing Gao

Determination of $\textit{B}$-meson distribution amplitudes from $\textit{B}$ → $\textit{π}$, $\textit{K}$, $\textit{D}$ transition form factors

We propose that generalized symmetries in some string-constructed QFTs are given by K-theory. We thus have $\textit{even-form}$ and $\textit{odd-form}$ symmetries determined by $\textit{K}$ ($\textit{∂X}$), the twisted K-theory as D-brane charges on the asymptotic boundary $\textit{∂X}$ of internal geometry $\textit{X}$ with twist class $\textit{N}$. For these QFTs, “$\textit{p-form symmetries}$” are no longer separately well-defined for individual $\textit{p}$, but are instead mixed together. We discuss 6D ADE-type (2,0) SCFTs and some 6d (1,0) LSTs as examples and demonstrate their twisted K-theoretic symmetries, and check that they are compatible with T-duality. We further point out, through explicit examples, that K-theory leads to symmetry extensions that cannot be detected by cohomology for Type II string theory on certain orbifolds of ℂ and ℂ . We also discuss the implications of these results in the dual brane descriptions.

Hao Zhang

Generalized symmetries in string-constructed QFTs via K-theory

<p>A time- and flavor-integrated amplitude analysis of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></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 to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">(</mo><msup><mi>K</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup><mo stretchy="false">)</mo><mo stretchy="false">(</mo><msup><mi>K</mi><mo>−</mo></msup><msup><mi>π</mi><mo>+</mo></msup><mo stretchy="false">)</mo></math> final state in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>K</mi><mo>*</mo></msup><mo stretchy="false">(</mo><mn>892</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup><msup><mover accent="true"><mi>K</mi><mo stretchy="false">¯</mo></mover><mo>*</mo></msup><mo stretchy="false">(</mo><mn>892</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup></math> region is presented, using <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mi>p</mi></math> collision data recorded with the LHCb detector in 2011–2018, corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>9</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>. The branching fractions of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></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 are measured relative to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msup><mi>D</mi><mo>−</mo></msup><msup><mi>π</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><mo stretchy="false">→</mo><msubsup><mi>D</mi><mi>s</mi><mo>−</mo></msubsup><msup><mi>π</mi><mo>+</mo></msup></math> modes, respectively. The corresponding longitudinal polarization fractions are found to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>f</mi><mi>L</mi><mi>d</mi></msubsup><mo>=</mo><mn>0.600</mn><mo>±</mo><mn>0.022</mn><mo>±</mo><mn>0.017</mn></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>f</mi><mi>L</mi><mi>s</mi></msubsup><mo>=</mo><mn>0.159</mn><mo>±</mo><mn>0.010</mn><mo>±</mo><mn>0.007</mn></math>, where the uncertainties are statistical and systematic, respectively. The theory-motivated ratio of the squared <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>B</mi><mi>s</mi><mn>0</mn></msubsup></math> to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></msup></math> longitudinally polarized decay amplitudes is found to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>L</mi><mrow><msup><mi>K</mi><mrow><mo>*</mo><mn>0</mn></mrow></msup><msup><mover accent="true"><mi>K</mi><mo stretchy="false">¯</mo></mover><mrow><mo>*</mo><mn>0</mn></mrow></msup></mrow></msub><mo>=</mo><mn>4.92</mn><mo>±</mo><mn>0.55</mn><mo>±</mo><mn>0.48</mn><mo>±</mo><mn>0.02</mn><mo>±</mo><mn>0.10</mn></math>, where the uncertainties are statistical, systematic, due to uncertainty of external mass and lifetime measurements, and due to knowledge of the fragmentation fraction ratio, respectively. This confirms the previously reported tension between experimental determinations and theoretical predictions of longitudinal polarization in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi><mo stretchy="false">→</mo><mi>V</mi><mi>V</mi></math> decays at the level of 4.4 standard deviations.</p>

Netherlands

R. Aaij

A.S.W. Abdelmotteleb

Switzerland

C. Abellan Beteta

F. Abudinén

T. Ackernley

A.A. Adefisoye

Spain

B. Adeva

M. Adinolfi

France

C. Agapopoulou

C.A. Aidala

Z. Ajaltouni

S. Akar

K. Akiba

P. Albicocco

J. Albrecht

R. Aleksiejunas

CERN

F. Alessio

P. Alvarez Cartelle

R. Amalric

Brazil

S. Amato

J.L. Amey

Y. Amhis

L. An

L. Anderlini

M. Andersson

P. Andreola

M. Andreotti

S. Andres Estrada

A. Anelli

D. Ao

C. Arata

F. Archilli

Z. Areg

M. Argenton

Costa Rica

S. Arguedas Cuendis

L. Arnone

A. Artamonov

M. Artuso

E. Aslanides

R. Ataíde Da Silva

M. Atzeni

B. Audurier

J.A. Authier

D. Bacher

Measurement of the branching fractions and longitudinal polarizations of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi>B</mi></mrow><mrow><mo stretchy="false">(</mo><mi>s</mi><mo stretchy="false">)</mo></mrow><mrow><mn>0</mn></mrow></msubsup><mo stretchy="false">→</mo><msup><mrow><mi>K</mi></mrow><mrow><mo>*</mo><mn>0</mn></mrow></msup><msup><mrow><mover accent="true"><mrow><mi>K</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mo>*</mo><mn>0</mn></mrow></msup></mrow></math> decays