The interference between amplitudes corresponding to different intermediate resonances plays an important role in generating large CP asymmetries in the phase space in multi-body decays of bottom and charmed mesons. In this study, we examine the CP violation in the decay channel $ {\overline{B}}^{0}\rightarrow K^{-}\pi^{+}\pi^{0} $ in the phase-space region where the intermediate resonances $ \overline{K}^{*}(892)^{0} $ and $ {\overline{K}^{*}_{0}(700)} $ dominate. In particular, the forward-backward asymmetry (FBA) and the CP asymmetry induced by FBA (FB-CPA), which are closely related to the interference effects between the two aforementioned resonances, are investigated. The nontrivial correlation between FBA and FB-CPA is analyzed. The analysis indicates that FB-CPAs around the resonance $ \overline{K}^{*}(892)^{0} $ can be as large as approximately 35%, which can be potentially accessible by Belle and Belle-II collaborations in the near future.

China

Jian-Yu Yang

Yu-Jie Zhao

Jing-Juan Qi

Zhen-Hua Zhang

The forward-backward asymmetry induced CP asymmetry in ${{\overline{B}}^{0}\rightarrow K^{-}\pi^{+}\pi^{0}}$ in phase space around the resonances ${{\overline{K}}^{*}(892)^{0}}$ and ${{\overline{K}}^{*}_{0}(700)}$ * Supported by National Natural Science Foundation of China (12475096, 12405115, 12192261) and Scientific Research Fund of Hunan Provincial Education Department (22A0319)

We focus our attention on two-qubit mixed states as initial states, and apply the geometric measure of quantum discord to investigate quantum discord properties in the background of a Schwarzschild black hole under phase damping, phase flip and bit flip channels, respectively. Several analytical complementary relationships based on quantum discords for bipartite subsystems are proposed. For the three channel noises, the behaviors of discords are similar, the accessible discords always degrade as the Hawking acceleration rising, but sudden death never occurs, while the inaccessible discords increase from zero monotonically. Interestingly, in the case of the bit flip channel and phase flip channel, the discords perform symmetrically with the decay probability rising.

Yuxuan Xiong

Zhiling Pi

Tinggui Zhang

Xiaofen Huang

Quantum discord of mixed states under noisy channels in the curved spacetime

We study the strong decay of $$D_{s0}^*(2317)^+$$ to $$D_s^+ \pi ^0$$ considering the coupled channels of $$D^0 K^+, D^+ K^0, D_s^+ \eta $$ and $$D_s^+ \pi ^0$$ within a picture for the interaction based on the local hidden gauge approach. We also address the problem of the radiative decay to $$D_s^{*+} \gamma $$ , using the same information obtained from the molecular picture. We obtain a strong width of the $$D_{s0}^*(2317)^+$$ of about $$77 \,\mathrm keV$$ from coupled channels interaction and a radiative decay of about $$1.7 \,\mathrm keV$$ . We also show that the extra consideration of $$\pi ^0-\eta $$ mixing can double the strong decay width to values around $$140 \,\mathrm keV$$ . The anomalous terms for the radiative decay are considered for the first time, but they are found negligible. We make a thorough discussion of this and other results to the light of the recent measurement of Belle for the ratio of these two decay modes, and make a call for the precise measurement of the two decay widths independently to clarify the present situation concerning the nature of the $$D_{s0}^*(2317)^+$$ state.

Pei-Sen Su

Wen-Tao Lyu

Wei-Hong Liang

Spain

Eulogio Oset

The $$D_{s0}^*(2317)^+$$ decay to $$D_s^+\pi ^0$$ and $$D_s^{*+}\gamma $$

An amplitude analysis of the decay $$ {D}^0\to {K}_S^0{\pi}^0{\pi}^0 $$ is performed to determine the relative magnitudes and phases of different intermediate processes. The analysis uses $\textit{e}$ $\textit{e}$ collision data collected at the center-of-mass energy of 3.773 GeV by the BESIII detector corresponding to an integrated luminosity of 20.3 fb . The absolute branching fraction of $$ {D}^0\to {K}_S^0{\pi}^0{\pi}^0 $$ is measured to be (1.026 $\textit{±}$ 0.008 $\textit{±}$ 0.009 )%. The dominant intermediate process is $$ {D}^0\to {\overline{K}}^{\ast }{(892)}^0\left(\to {K}_S^0{\pi}^0\right){\pi}^0 $$ , with a branching fraction of (4.10 $\textit{±}$ 0.10 $\textit{±}$ 0.07 ) $\textit{×}$ 10 .

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

United States

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

South Korea

S. Choi

X. Chu

G. Cibinetto

F. Cossio

United Kingdom

J. Cottee-Meldrum

J. Cui

H. Dai

J. Dai

A. Dbeyssi

R. Boer

F. Mori

D. Dedovich

C. Deng

Z. Deng

A. Denig

I. Denysenko

M. Destefanis

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

Amplitude analysis and branching fraction measurement of the decay $$ {D}^0\to {K}_S^0{\pi}^0{\pi}^0 $$

We perform a unified description of the experimental data of the $$\pi ^+\pi ^-$$ invariant mass spectra of $$B_s^0 \rightarrow \psi (2S) \pi ^+\pi ^-$$ , the $$\pi ^+\pi ^-$$ and $$K^+ K^-$$ invariant mass spectra of $$B_s^0 \rightarrow X(3872) \pi ^+\pi ^- (K^+ K^-)$$ , and the ratio of branch fractions $$\mathcal {B}[B_s^0 \rightarrow X(3872)(K^+K^-)_{\mathrm{non-}\phi }]/ \mathcal {B}[B_s^0 \rightarrow X(3872)\pi ^+ \pi ^-]$$ . The strong final state interactions between the two pseudoscalars are taken into account using a parametrization fulfilling unitarity and analyticity. We find that there is universality in the coupling constants for $$B_s^0 \rightarrow \psi (2S) \pi ^+\pi ^-$$ and $$B_s^0 \rightarrow J/\psi \pi ^+\pi ^-$$ processes. While the couplings of $$B_s^0 \rightarrow X(3872) \pi ^+\pi ^-$$ are about half of magnitude smaller than the couplings of $$B_s^0 \rightarrow \psi (2S) \pi ^+\pi ^-$$ , which indicates that the $\textit{X}$(3872) is different from a pure charmonium state. Furthermore, we find that the $$f_0(1500)$$ plays an important role in the $$B_s^0 \rightarrow \psi (2S) \pi ^+\pi ^-$$ and the $$B_s^0 \rightarrow X(3872) \pi ^+\pi ^- (K^+ K^-)$$ processes, though the phase space of $$B_s^0 \rightarrow X(3872) f_0(1500)$$ is small. Also we predict the ratio of branch fractions $$\mathcal {B}[B_s^0 \rightarrow \psi (2S)(K^+K^-)_{\mathrm{non-}\phi }]/ \mathcal {B}[B_s^0 \rightarrow \psi (2S)\pi ^+ \pi ^-]$$ and the $$K^+ K^-$$ invariant mass distribution of $$B_s^0 \rightarrow \psi (2S)K^+K^-$$ .

Yun-Hua Chen

Unified study of $$B_s^0 \rightarrow X(3872) \pi ^+\pi ^- (K^+ K^-)$$ and $$B_s^0 \rightarrow \psi (2S) \pi ^+\pi ^- (K^+ K^-)$$ processes

Hidden-charm pentaquark states with double strangeness, $$P_{css}$$ , have been predicted within the framework of unitary coupled-channel dynamics. In this work, we theoretically investigate the potential to observe these states in the decays $$\Lambda _b\rightarrow J/\psi \Xi ^-K^+$$ and $$\Xi _b\rightarrow J/\psi \Xi ^-\pi ^+$$ . In this framework, these pentaquark configurations couple strongly to the $$J/\psi \Xi $$ channel, as well as to other vector-baryon channels with the $$\bar{c} c s s n$$ flavor structure, making these decay modes promising for their observation through the corresponding invariant-mass distributions. Our analysis begins with the identification of the dominant weak decay mechanisms, followed by hadronization into meson-baryon channels, connected through flavor symmetry. Final-state interactions are then incorporated to dynamically generate the full amplitude, accounting for the formation of the pentaquark states. We compare our results with recent LHCb measurements of the $$J/\psi \Xi ^-$$ mass distribution and find that, given the predicted pentaquark width of about 10 MeV in this channel, the state is too narrow to be resolved with the current experimental resolution, but it would become visible with significantly improved mass precision.

L. Roca

J. Song

E. Oset

Study of hidden-charm, doubly-strange pentaquarks in $$\Lambda _b\rightarrow J/\psi \Xi ^- K^+$$ and $$\Xi _b\rightarrow J/\psi \Xi ^- \pi ^+$$

Symmetry studies represent one of the most promising frontiers in particle physics research. This investigation focuses on exploring P and $\rm CP $ symmetries in the charm system through the measurement of asymmetry decay parameters in the three-body decay of $ \Xi_c^{+} $ . By incorporating electron and positron beam polarization effects and utilizing the helicity formalism, we characterize the decay of $ \Xi_c^{+} $ and its secondary hyperons through asymmetry decay parameters. The complete angular distribution formula for these decays is systematically derived. Our study evaluates the sensitivity of the asymmetry parameters for the $ \Xi_c^{+} \to \Xi^{-}\pi^{+}\pi^{+} $ decay channel under various data sample sizes and beam polarization scenarios. The findings establish a robust theoretical framework for future experimental studies at the Super Tau-Charm Facility, providing valuable insights for symmetry investigations in the charm sector.

Yunlu Wang

Yunlong Xiao

Pengcheng Hong

Ronggang Ping

Study of P and CP symmetries in ${ \boldsymbol\Xi^{\bf +}_{\boldsymbol c}\rightarrow \boldsymbol\Xi^-\boldsymbol\pi^+\boldsymbol\pi^+ }$ at electron-positron collider

In this study, we investigate the isospin-violating decays of $ B_{c}(1P)^{+}\to B_{c}^{(*)+}\pi^{0} $ , which may provide additional information for the determination of the properties of $ B_{c}(1P)^{+} $ , the first orbital excitation states of the $B_c $ meson. By assuming a dual relation between the $\textit{U}$(1) anomaly soft-gluon coupling for $ B_{c}(1P)^{+}\to B_{c}^{(*)+}\pi^{0} $ and the intermediate meson loop transitions, we can quantify the isospin-violating decay effects for these four $\textit{P}$-wave states. We observe that the partial decay width of $ B_{c0}^{*+}\to B_{c}^{+}\pi^{0} $ is approximately three orders of magnitude larger than that for $ B_{c2}^{*+}\to B_{c}^{+}\pi^{0} $ . This indicates that $ B_{c0}^{*+} $ can be established in the $ B_{c}^{+}\pi^{0} $ decay channel as a single state. Meanwhile, the two axial-vector states $ B_{c1}^{+}/B_{c1}'^{+} $ can be possibly identified in $ B_{c1}^{+}/B_{c1}'^{+}\to B_{c}^{*+}\pi^{0} $ with comparable strengths. Although these isospin-violating decays are observed to be small, the theoretical predictions should be useful for guiding future experimental efforts.

Jun Wang

Qiang Zhao

Predictions for the isospin-violating decays of ${{\boldsymbol B}_{\boldsymbol c}({\boldsymbol{1P}})^{\bf +}{\bf\to}{\boldsymbol B}_{\boldsymbol c}^{({\bf *})+}\boldsymbol\pi^{\bf 0}}$ * Supported, in part, by the National Natural Science Foundation of China (12235018), DFG and NSFC funds to the Sino-German CRC 110 'Symmetries and the Emergence of Structure in QCD' (12070131001, DFG Project-ID 196253076), National Key Basic Research Program of China (2020YFA0406300) and Strategic Priority Research Program of Chinese Academy of Sciences (XDB34030302)

We present a measurement of the time-dependent $\textit{CP}$ asymmetry in $${B}^{0}\to {K}_{\text{S}}^{0}{\pi }^{+}{\pi }^{-}\gamma $$ decays using a data set of 365 fb recorded by the Belle II experiment and the final data set of 711 fb recorded by the Belle experiment at the Υ(4S) resonance. The direct and mixing-induced time-dependent $\textit{CP}$ violation parameters $\textit{C}$ and $\textit{S}$ are determined along with two additional quantities, $\textit{S}$ and $\textit{S}$ , defined in the two halves of the $${m}^{2}\left({K}_{\text{S}}^{0}{\pi }^{+}\right)-{m}^{2}\left({K}_{\text{S}}^{0}{\pi }^{-}\right)$$ plane. The measured values are $\textit{C}$ = $\textit{−}$0$\textit{.}$17 $\textit{±}$ 0$\textit{.}$09 $\textit{±}$ 0$\textit{.}$04, $\textit{S}$ = $\textit{−}$0$\textit{.}$29 $\textit{±}$ 0$\textit{.}$11 $\textit{±}$ 0$\textit{.}$05, $\textit{S}$ = −0$\textit{.}$57 $\textit{±}$ 0$\textit{.}$23 $\textit{±}$ 0$\textit{.}$10 and $\textit{S}$ = 0$\textit{.}$31 $\textit{±}$ 0$\textit{.}$24 $\textit{±}$ 0$\textit{.}$05, where the first uncertainty is statistical and the second systematic.

M. Abumusabh

I. Adachi

L. Aggarwal

H. Ahmed

Y. Ahn

H. Aihara

N. Akopov

S. Alghamdi

M. Alhakami

K. Amos

N. Anh Ky

D. Asner

H. Atmacan

T. Aushev

R. Ayad

V. Babu

S. Bahinipati

P. Bambade

Sw. Banerjee

M. Barrett

M. Bartl

J. Baudot

A. Beaubien

F. Becherer

J. Becker

J. Bennett

V. Bertacchi

E. Bertholet

M. Bessner

S. Bettarini

V. Bhardwaj

B. Bhuyan

T. Bilka

D. Biswas

A. Bobrov

D. Bodrov

J. Borah

A. Boschetti

A. Bozek

M. Bračko

P. Branchini

T. Browder

A. Budano

S. Bussino

Q. Campagna

M. Campajola

G. Casarosa

C. Cecchi

P. Cheema

L. Chen

C. Cheshta

H. Chetri

J. Chin

K. Chirapatpimol

H.E. Cho

K. Cho

S.J. Cho

S.K. Choi

S. Choudhury

J. Colorado-Caicedo

L. Corona

E. Cruz-Burelo

S. Motte

Measurement of time-dependent $\textit{CP}$ asymmetries in $${B}^{0}\to {K}_{\text{S}}^{0}{\pi }^{+}{\pi }^{-}\gamma $$ decays at Belle and Belle II