High-precision regression of physical parameters from black hole images generated by General Relativistic Ray Tracing (GRRT) is essential for investigating spacetime curvature and advancing black hole astrophysics. However, owing to limitations in observational resolution, high observational costs, and imbalanced distributions of positive and negative samples, black hole images often suffer from data scarcity, sparse parameter spaces, and complex structural characteristics. These factors pose significant challenges to conventional regression methods based on simplified physical models. To overcome these challenges, this study introduces the Multiscale Adaptive Network (MANet), a novel regression framework grounded in deep learning. MANet integrates an Adaptive Channel Attention (ACA) module to selectively enhance features in physically informative regions. Meanwhile, a Multiscale Enhancement Feature Pyramid (MEFP) is employed to capture fine-grained spatial structures, such as photon rings and accretion disks, while alleviating information loss due to downsampling. Experimental evaluations on GRRT-simulated datasets demonstrate that MANet substantially improves parameter estimation accuracy and generalization capability in high-dimensional parameter spaces, outperforming existing baseline approaches. This framework presents a promising avenue for high-precision parameter regression in Event Horizon Telescope (EHT) data analysis and broader astrophysical imaging applications characterized by sparse and noisy data.

China

Jialei Wei

Ao Liu

Dejiang Li

Cuihong Wen

Physical parameter regression from black hole images using a multiscale adaptive neural network * Supported by the Natural Science Foundation of Hunan Province under grant No. 2023JJ30384; the National Natural Science Foundation of China under Grants No. 12374408; the University Students' Innovation and Entrepreneurship Training Program Project

The study of extra charged gauge bosons beyond the Standard Model has always been of great interest. Future muon colliders will have a significant advantage in discovering exotic particles. In this paper, by studying the $ \mu^+ \mu^- \to W^{\prime +} W^{\prime -} \to e^+ e^- n_e \bar{n}_e $ process, we explore the properties of $ W^\prime $ in the alternative left-right model. The cross section and angular distribution of the final electron are investigated in a scenario of different $ W^\prime $ masses and right-handed coupling constants. The forward-backward asymmetry is also an important observable to reflect the properties of $ W^\prime $ . We provide a method to effectively suppress the background processes by imposing constraints on the transverse momentum $ P_T $ and azimuthal angle of the final-state electrons $\textit{α}$. With cuts of $ 600 \lt P_T \lt 3500 $ GeV and $ 0.5 \lt \alpha \lt 3 $ , the significance exceeds 5$\textit{σ}$ for 4.8 TeV $ W^\prime $ at a collision energy of 10 TeV.

Liuxin Zhao

Honglei Li

Zhi-Long Han

Fei Huang

Xinyi Yan

Extra charged gauge boson $\textit{W}$′ in Alternative Left-Right Model at future muon collider * This work is supported by the Natural Science Foundation of Shandong Province (ZR2022MA065, ZR2024QA138), and University of Jinan Disciplinary Cross-Convergence Construction Project 2024 (XKJC-202404)

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.

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)

In this manuscript, we examine geometrical and physical properties of wormhole ( $$\mathcal{W}\mathcal{H}$$ ) solutions with monopole charge by considering three distinct shape function models in power-law gravity, i.e., Starobinsky $\textit{f}$($\textit{R}$) gravity, where $\textit{R}$ is Ricci scalr. The modified gravitational field equations are solved under the assumption of anisotropic energy–momentum tensor ( $$\mathcal {EMT}$$ ), with particular attention given to the role of exotic matter ( $$\mathcal{E}\mathcal{M}$$ ) in sustaining these solutions. The impact of the global monopole charge ( $$\mathcal {GMC}$$ ) is examined in detail, revealing that higher monopole charges enlarge the throat radius and produce flatter embedding surfaces through two and three dimensional embedding diagrams, thereby affecting both traversability and structural stability. A comprehensive investigation of physical quantities, energy conditions and stability analysis is carried out using several physical and geometrical criteria, including the adiabatic index approach, Herrera’s cracking criterion, and causality conditions approach, along with anisotropic effects. Moreover, the total amount of $$\mathcal{E}\mathcal{M}$$ is quantified through the volume integral quantifier method. These findings highlight supportive directions for future explorations of exotic spacetime structures in both theoretical and astrophysical contexts.

Azerbaijan

Pakistan

M. Yousaf

H. Asad

Kashif Yasir

Oman

S. Maurya

Saudi Arabia

Akram Ali

Uzbekistan

Farruh Atamurotov

Global monopole induced wormholes in power-law gravity: stability and physical viability

We present the first lattice QCD calculations of the isovector helicity transverse momentum-dependent parton distribution function (TMDPDF) and the flavor-dependent unpolarized TMDPDFs for up and down quarks in the proton. Our computations utilize domain-wall fermion discretization with physical quark masses. Employing Coulomb-gauge-fixed quark correlation functions within the large-momentum effective theory framework, we access nonperturbative transverse quark separations <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>b</mi><mi>T</mi></msub></math> up to approximately 1 fm, corresponding to transverse momenta as low as 200 MeV. Based on the quasi-TMD factorization theorem, we construct renormalization-group–invariant ratios that are equal to the corresponding light-cone TMDPDF ratios. At moderate <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>x</mi></math>, our results reveal that the isovector helicity and unpolarized TMDPDFs exhibit nearly identical transverse structure up to a normalization factor, and the unpolarized distributions display only mild flavor dependence. These findings not only support key trends observed in recent global analyses but also provide robust, nonperturbative constraints that can distinguish between different parameterizations. This Letter establishes a first-principles benchmark for TMDPDFs, offering valuable input for ongoing and future experimental efforts to map the proton’s three-dimensional structure.

Dennis Bollweg

Xiang Gao

Swagato Mukherjee

Yong Zhao

Lattice QCD Benchmark of Proton Helicity and Flavor-Dependent Unpolarized Transverse Momentum-Dependent Parton Distribution Functions at Physical Quark Masses

We study the S-wave interactions between the nucleon ( <italic>N</italic>) and the triply charmed Omega baryon (&#937; <inf>ccc</inf>) using (2+1)-flavor lattice QCD with a physical pion mass ( <italic>m<inf>&#960;</inf></italic>&#8239;&#8771;&#8239;137.1 MeV) on a lattice volume &#8239;&#8771;&#8239;(8.1&#8201;fm) 3. The charm quark is implemented with a relativistic heavy-quark action at its physical mass. Employing the time-dependent HAL QCD method, the <math altimg='si29.svg'><mrow><mi>N</mi><mspace width='0.16em' /><mo linebreak='goodbreak'>&#8722;</mo><mspace width='0.16em' /><msub><mstyle mathvariant='normal'><mi>&#937;</mi></mstyle><mrow><mi mathvariant='normal'>ccc</mi></mrow></msub></mrow></math> potentials in the spin-1 ( 3S <inf>1</inf>) and spin-2 ( 5S <inf>2</inf>) channels are extracted. In both channels, overall attraction is found with the scattering parameters, <math altimg='si30.svg'><mrow><msub><mi>a</mi><mn>0</mn></msub><mo linebreak='goodbreak'>=</mo><mn>0.56</mn><mrow><mo>(</mo><mn>0.13</mn><mo>)</mo></mrow><mrow><mo stretchy='true'>(</mo><msubsup><mrow /><mrow><mo>&#8722;</mo><mn>0.03</mn></mrow><mrow><mo>+</mo><mn>0.26</mn></mrow></msubsup><mo stretchy='true'>)</mo></mrow></mrow></math> fm and <math altimg='si31.svg'><mrow><msub><mi>r</mi><mrow><mi mathvariant='normal'>eff</mi></mrow></msub><mo linebreak='goodbreak'>=</mo><mn>1.60</mn><mrow><mo>(</mo><mn>0.05</mn><mo>)</mo></mrow><mrow><mo stretchy='true'>(</mo><msubsup><mrow /><mrow><mo>&#8722;</mo><mn>0.12</mn></mrow><mrow><mo>+</mo><mn>0.04</mn></mrow></msubsup><mo stretchy='true'>)</mo></mrow></mrow></math> fm for the 3S <inf>1</inf> channel, and <math altimg='si32.svg'><mrow><msub><mi>a</mi><mn>0</mn></msub><mo linebreak='goodbreak'>=</mo><mn>0.38</mn><mrow><mo>(</mo><mn>0.12</mn><mo>)</mo></mrow><mrow><mo stretchy='true'>(</mo><msubsup><mrow /><mrow><mo>&#8722;</mo><mn>0.00</mn></mrow><mrow><mo>+</mo><mn>0.25</mn></mrow></msubsup><mo stretchy='true'>)</mo></mrow></mrow></math> fm and <math altimg='si33.svg'><mrow><msub><mi>r</mi><mrow><mi mathvariant='normal'>eff</mi></mrow></msub><mo linebreak='goodbreak'>=</mo><mn>2.04</mn><mrow><mo>(</mo><mn>0.10</mn><mo>)</mo></mrow><mrow><mo stretchy='true'>(</mo><msubsup><mrow /><mrow><mo>&#8722;</mo><mn>0.22</mn></mrow><mrow><mo>+</mo><mn>0.03</mn></mrow></msubsup><mo stretchy='true'>)</mo></mrow></mrow></math> fm for the 5S <inf>2</inf> channel, indicating the absence of a dibaryon bound state. The extracted potentials are further decomposed into spin-independent and spin-dependent components. The spin-independent potential is a dominant component and features a short-range attractive core and a long-range attractive tail, while the spin-dependent potential shows short-range attraction (repulsion) in the spin-1 (spin-2) channel. Qualitative comparisons with previous studies of the <math altimg='si4.svg'><mrow><mi>N</mi><mspace width='0.16em' /><mo linebreak='goodbreak'>&#8722;</mo><mspace width='0.16em' /><mi>J</mi><mo linebreak='goodbreak'>/</mo><mi>&#968;</mi></mrow></math> and <math altimg='si34.svg'><mrow><mi>N</mi><mspace width='0.16em' /><mo linebreak='goodbreak'>&#8722;</mo><mspace width='0.16em' /><msub><mstyle mathvariant='normal'><mi>&#937;</mi></mstyle><mrow><mi mathvariant='normal'>sss</mi></mrow></msub></mrow></math> systems at <italic>m<inf>&#960;</inf></italic>&#8239;&#8771;&#8239;146 MeV are provided, emphasizing the role of heavy-hadron chromo-polarizability arising from soft-gluon exchange between the nucleon and flavor-singlet hadrons. The charm quark mass dependence of the <math altimg='si35.svg'><mrow><mi>N</mi><mspace width='0.16em' /><mo linebreak='goodbreak'>&#8722;</mo><mspace width='0.16em' /><msub><mstyle mathvariant='normal'><mi>&#937;</mi></mstyle><mrow><mrow><mi mathvariant='normal'>c</mi></mrow><mi>c</mi><mi>c</mi></mrow></msub></mrow></math> potential is investigated as well.

Japan

Liang Zhang

Takumi Doi

Yan Lyu

Tetsuo Hatsuda

Yu-Gang Ma

Probing nucleon-Ω <inf>ccc</inf> interaction via lattice QCD at physical quark masses

Within the framework of the next-to-minimal supersymmetric (SUSY) extension of the Standard Model (SM) with a local B-L gauge symmetry (N-B-LSSM), we study lepton flavor violating (LFV) $ \tau\rightarrow e M^+ M^- $ decays: $ \tau \rightarrow e \pi^+\pi^- $ , $ \tau \rightarrow e \pi^+K^- $ , and $ \tau \rightarrow e K^+K^- $ . Based on the latest experimental data, the influence of different sensitive parameters on the branching ratios is considered. It can be seen from the numerical analysis that the main sensitive parameters and LFV sources are non-diagonal elements corresponding to the initial and final leptons. This work can provide a basis for discovering the existence of new physics (NP).

Rong-Zhi Sun

Shu-Min Zhao

Shuang Di

Portugal

Xing-Xing Dong

Study of ${\boldsymbol\tau\rightarrow {\boldsymbol e M^+ M^-}}$ decays in N-B-LSSM * Supported by National Natural Science Foundation of China (NNSFC) (12075074), Natural Science Foundation of Hebei Province (A2023201040, A2022201022, A2022201017, A2023201041), Natural Science Foundation of Hebei Education Department (QN2022173), Post-graduate's Innovation Fund Project of Hebei University (HBU2024SS042), the Project of the China Scholarship Council (CSC) (202408130113). X. Dong acknowledges support from Fundação para a Ciência e a Tecnologia (FCT, Portugal) through the projects CFTP FCT Unit (UIDB/00777/2020, UIDP/00777/2020)

This study investigates the intrinsic electric dipole moment (EDM) of the $\textit{τ}$ lepton, which is an important quantity in the search for physics beyond the Standard Model (BSM). In preparation for future measurements at the Super Tau-Charm Facility (STCF), we employ Monte Carlo simulations of the $ e^+e^- \rightarrow \tau^+\tau^- $ process and optimize the analysis methodology for EDM extraction. Machine learning techniques are implemented to efficiently identify signal events ( $ \tau^\pm\rightarrow \pi^\pm\pi^0\nu_\tau $ ), which result in a significant improvement in signal-to-noise ratio. Our optimized event selection algorithm achieves 80.0% signal purity with 6.3% efficiency. We develop an analytical approach for $\textit{τ}$ lepton momentum reconstruction and derive the squared spin density matrix along with optimal observables, which maximize the sensitivity to $ d_\tau $ . The relationship between these observables and the EDM is established with the estimated sensitivity of $ |d_\tau| \lt 3.89\times 10^{-18}\,e\cdot\mathrm{cm} $ at a 68% confidence level. These results provide a foundation for future experimental measurements of the $\textit{τ}$ lepton EDM in STCF experiments.

Xulei Sun

Yongcheng Wu

Xiaorong Zhou

Sensitivity study of the tau lepton electric dipole moment at the Super Tau-Charm Facility * Supported by the National Key R&D Program of China (2022YFA1602200, 2023YFA1607200); the National Natural Science Foundation of China (NSFC) (12341501, 12341503, 12341504); the international partnership program of the Chinese Academy of Sciences (211134KYSB20200057). Xulei Sun is supported by the Undergraduate Research Program of the University of Science and Technology of China and the Xinhe Scholar Program of the School of the Gifted Young

Recent anomalies observed in $ e^+e^- $ nuclear transitions of $ ^8 {{\rm{Be}}} $ , $ ^4 {\rm{He}} $ , and $ ^{12} {\rm{C}} $ by the ATOMKI collaboration may hint at the existence of a vector boson with a mass around 17 MeV, which is referred to as X17. If it exists, this boson would affect similar processes in particle physics, including the Dalitz decays of vector mesons. Recently, the BESIII collaboration measured the Dalitz decay $ D^{*0}\to D^0e^+e^- $ for the first time and reported a $ 3.5\sigma $ excess over the theoretical prediction based on the vector meson dominance (VMD) model. This excess may be another signal of X17. In this study, we investigate the possible effects of X17 on the Dalitz decays $ D^*_{(s)}\to D_{(s)}e^+e^- $ , $ B^*_{(s)}\to B_{(s)}e^+e^- $ , and $ J/\psi\to \eta_ce^+e^- $ . The required hadronic form factors are calculated within the framework of our covariant confined quark model without relying on heavy quark effective theory or the VMD model. We present predictions for the Dalitz decay widths and the ratios $ R_{ee}(V)\equiv \Gamma(V\to Pe^+e^-)/\Gamma(V\to P\gamma) $ within the standard model and in several new physics scenarios involving modifications attributed to X17. Our results are compared with other theoretical calculations.

Vietnam

C.T. Tran

M.A. Ivanov

A.T.T. Nguyen

Probing the ATOMKI X17 vector boson using Dalitz decays $\textit{V}$ → $\textit{Pe}$ $^{+}$ $\textit{e}$ $^{−}$ * Supported by Ho Chi Minh City University of Technology and Education (T2024-65)

Vector-like quarks (VLQs) feature in new physics models beyond the standard model (SM) to address certain problems it faces. In this study, we investigate the pair production of TeV-scale vector-like $\textit{B}$ quark (VLQ-$\textit{B}$) at the proposed 3 TeV compact linear collider (CLIC) using a simplified effective lagrangian framework. We consider the decay modes of $ B\rightarrow bZ $ and $ B\rightarrow bh $ , coupled with the hadronic decay of $\textit{Z}$ and $\textit{h}$ bosons. The large mass of VLQ-$\textit{B}$ results in highly boosted $\textit{Z}$ or $\textit{h}$ bosons, which tend to form fat-jets. Using detector simulation of the signal and background events, along with jet clustering employing a large radius $\textit{R}$, we conduct signal-background analyses. Exclusion limits at the 95% confidence level and 5 $ \sigma $ discovery prospects are obtained assuming an integrated luminosity of 5 ab$^{−1}$.

Shuo Yang

Yi-Hang Wang

Peng-Bo Zhao

Ji-Long Ma

Search for heavy vector-like $\textit{B}$ quark via pair production in fully hadronic channels at CLIC * Supported in part by the National Natural Science Foundation of China (12147214, 11905093), Basic Research Project of Liaoning Provincial Department of Education for Universities (LJKMZ20221431), and Teaching Reform Research Project for graduates of Liaoning Normal University