The 2026 International Workshop on the High Energy Circular Electron Positron Collider

21 Oct 2026, 09:00 → 26 Oct 2026, 18:15 Asia/Shanghai

Sheraton Shanghai Jiading Hotel

Xiaolong Wang (Fudan University), Junfeng Chen (Shanghai Institute of Ceramics, Chinese Academy of Sciences（中国科学院上海硅酸盐研究所）), Jianchun Wang (IHEP), Miao He (IHEP), Jiayin Gu (Fudan University)

The 2026 International Workshop on the High-Energy Circular Electron-Positron Collider (CEPC2026) will be held in Shanghai from October 22 to 26, 2026. The event is jointly hosted by Fudan University (FDU), the Shanghai Institute of Ceramics (SIC/CAS), and the Institute of High Energy Physics (IHEP/CAS). This annual workshop brings together scientists from around the world to explore the physics potential of future high-energy circular electron-positron colliders . It fosters international collaboration to optimize accelerator and detector designs, and advances R&D on critical technologies.

The workshop will feature plenary, parallel, and poster sessions. All plenary presentations will be invited talks, while poster presentations will be selected from submitted abstracts. The oral presentations in the parallel sessions will be drawn from both invited speakers and submitted abstracts. We especially encourage participation from graduate students and postdocs. Outstanding posters will be recognized with awards, chosen by a selection committee composed of Scientific Program Committee (SPC) members, session conveners, and local organizers.

The program will also showcase exhibitions by leading industrial partners, offering attendees a firsthand look at cutting-edge innovations and advanced prototypes, along with focused discussions on technology research and development, and strategies for industrialization readiness.

Deadline for abstract submission is September 6, 2026. Deadline for registration is September 30, 2026. For information about visa applications, please visit the dedicated page at https://indico.ihep.ac.cn/event/cepc2026/, which is also accessible via the registration page. 

For assistance, please contact our support email address cepcws2026@ihep.ac.cn. All payments will be processed on-site, and any official notices will be sent exclusively from this address.  

CEPC2026 WeChat Group QR Code

Wednesday, 21 October

14:00 → 20:00 Registration

Thursday, 22 October

08:30 → 08:40 Welcome

Convener: XiaoLong Wang (Fudan University)

08:30 Welcome Opening

08:40 → 10:10 Plenary: 1

Thursday Morning: Grand Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

Monday Afternoon: Junior Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

08:40 Exploring the Electroweak scale with precision

Speaker: Patrick Meade (Stony Brook University)

09:20 Strategy of the CEPC

Speaker: Xinchou LOU (高能所)

09:50 Discussion

10:10 → 10:40 Coffee break

10:40 → 12:40 Plenary: 2

Thursday Morning: Grand Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

Monday Afternoon: Junior Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

10:40 CEPC accelerator - technologies & potential contribution to FCC-ee

Speaker: Jie GAO (IHEP)

11:10 Status and plan of the AGORA detector

Speaker: Joao Guimaraes da Costa

11:40 Progress towards implementation of Agentic AI

Speaker: Mihoko Nojiri (KEK)

12:10 Status of FCC-ee

Speaker: Frank Zimmermann (CERN)

12:40 → 14:00 Lunch break

14:00 → 15:40 Accelerator: 1

Zoom Link, ID: 94805716496, Code: 217749

14:00 CEPC accelerator EDR status

Speaker: Jie Gao

14:20 Historical Review of the DAFNE

Speaker: Catia Milardi

14:40 CEPC collider ring beam dynamics EDR status

Speaker: Yiwei Wang

15:00 CEPC collider ring error analysis with anti-solenoid effects

Speaker: Bin Wang

15:20 CEPC IP tunning status

Speaker: Yuanyuan Wei

14:00 → 15:30 CIPC & Industrial Partnerships: 1

Zoom Link, ID: 934 7906 6977, Code: 522727

14:00 → 15:35 Higgs Physics: 1

Zoom Link, ID:99229612134, Code: 887914

Convener: Mingshui CHEN (IHEP)

14:00 Parton spin correlations and CP properties in Higgs boson decay at future lepton colliders

N/A

Speaker: Ying-Ying Li (IHEP)

14:25 Towards Detector-Level Probes of Gluon Spin Correlations in Higgs Decays with the CEPC AGORA Detector

Partonic spin correlations in Higgs boson decays provide a novel opportunity to probe the CP structure of the Higgs--gluon coupling at future lepton colliders. Translating this physics potential into a realistic measurement requires the identification of different gluon splitting modes, whose contributions can otherwise largely cancel in inclusive observables. In this work, we take a step towards a detector-level measurement using full-simulation samples of the CEPC AGORA detector at $\sqrt{s}=240~\mathrm{GeV}$. Building on the jet-tagging framework developed for the AGORA detector studies, we develop an extended seven-class jet tagger capable of distinguishing quark flavors and different gluon splitting modes. This enables the separation of $H\to gg$ events into $gggg$, $ggq\bar{q}$, and $q\bar{q}q\bar{q}$ topologies, providing the experimental basis for measuring their event rates and spin-sensitive observables. The study establishes a pathway towards detector-level measurements of gluon spin correlations and, ultimately, direct constraints on the CP structure of the Higgs--gluon coupling at the CEPC.

Speaker: Shahd Younes

14:45 CPV mixing angle measurement in Higgs to ττ decays at 240 GeV CEPC

If the SM-like Higgs boson is realized as a mixture of scalar and pseudoscalar states, the CP violating mixing angle can be measured through various Higgs boson production and decay channels. Here we consider Higgs to tau-pair decays, at 240 GeV CEPC with 5.6 ab-1 of simulated data. Preliminary projections of the absolute uncertainty of the mixing angle are given, for the Higgs boson production in Higgsstrahlung, where the primary Z0 boson decays inclusively.

Speaker: Ivanka Bozovic (Vinca Institute of Nuclear Sciences)

15:10 Energy-Correlator-Inspired Tau Polarimetry for Higgs CP and Precision Weak Mixing Angle Measurements at Lepton Colliders

The azimuthal angle difference between the decay planes of the two tau leptons in h to tau+ tau- probes charge-parity (CP) violation in the Higgs-tau Yukawa coupling. In the dominant hadronic channel tau+- to rho+- nu, the spin-analyzing power is suppressed by the mixture of longitudinal and transverse rho polarizations. We propose an energy-correlator (E4C) inspired method that weights each event by a power of the pion energy asymmetry in rho+- to pi+- pi0, preferentially selecting longitudinal rho mesons. Applied to e+ e- to Z to tau+ tau-, the weighting enhances the sensitivity of the visible-energy spectrum to the tau polarization P tau, and hence to the effective weak mixing angle sinthetaw. In a parton-level template-fit study of Z to tau+ tau- samples generated with MadGraph5 using a tau-decay UFO model, the single-sided weight reduces the statistical uncertainty on sinthetaw by 15 percent at the optimal exponent, equivalent to a 35 percent increase in integrated luminosity. Splitting the samples into forward and backward hemispheres yields a second, independent estimator whose combination improves the precision by a further factor of 1.4. These results establish E4C weighting as a simple and robust tool for precision tau physics at future lepton colliders.

Speaker: Anjan Kumar Barik (TDLI)

14:00 → 15:30 Silicon Detectors: 1

Zoom Link, ID: 91011235165, Code: 983836

15:30 → 16:00 Coffee break

16:00 → 18:00 Accelerator: 2

Zoom Link, ID: 94805716496, Code: 217749

16:00 On SuperKEKB status and international collaboration

Speaker: Makoto Tobiyama

16:20 CEPC ground motion status

Speaker: Fang Yan

16:40 CEPC booster and damping ring (DR) EDR status

Speaker: Dou WANG (IHEP)

17:00 CEPC Booster Magnet production line and dipole+sextupole magnets

Speakers: Wen Kang, Zhihui Mu

17:20 CEPC collider ring magnets EDR activities

Speaker: Mei Yang

16:00 → 18:00 CIPC & Industrial Partnerships: 2

Zoom Link, ID: 934 7906 6977, Code: 522727

16:00 → 18:05 Higgs Physics: 2

Zoom Link, ID:99229612134, Code: 887914

Convener: Dr Enkhbat Tsedenbaljir (Institute of Physics and Technology, Mongolian Academy of Sciences)

16:00 Deep-learning boosted hadronic Higgs precise measurements at future e+e− Higgs factories

Precise measurements of Higgs decays into quarks and gluons are essential for probing the Yukawa couplings of the Higgs boson and testing the flavor structure of the Standard Model. We investigate the process e+e− → ZH at √s = 240 GeV at a future e+e− Higgs factory, taking the CEPC design as a benchmark. The analysis focuses on events with Z → νν¯/mu+mu- and hadronic Higgs decays H → b¯b, cc¯, ss¯ and gg. Jet flavor is identified using state-of-the-art particle-level deep neural network taggers (ParticleNet, Particle Transformer and More-Interaction Particle Transformer), whose per-jet outputs are combined with global event observables in a two-stage analysis employing XGBoost classifiers to separate the four Higgs decay modes from the dominant two- and four-fermion Standard Model backgrounds. Assuming an integrated luminosity of 20 ab−1, we present a quantitative sensitivity estimation corresponding to a statistical significance of about 1.3σ for H → s¯s. These results highlight the potential of deep-learning-based jet flavor tagging for precision studies of Higgs decays at future e+e− Higgs factories.

Speaker: Chunxiang Zhu (Shanghai Jiao Tong University)

16:25 Towards precision frontier: development of reconstruction and analysis tools for the CEPC experiment

The CEPC experiment is aimed at high precision measurements, which opens a possibility to find deviations from the Standard Model predictions and indications of new physics. The proposed CEPC detectors incorporate many technological achievements accompanied by advanced reconstruction tools. In this talk, further enhancements of Higgs boson studies with recoil mass technique are described. The correction for lepton final state radiation is demonstrated to improve Z boson mass resolution in its decays to electrons or muons. The improvement of Higgs mass distribution can be also achieved by the correction of recoil mass to the mu+mu- system in the process e+e- -> H Z(mu+mu-) for the energetic ISR photon reconstructed in the ECAL. A novel approach is discussed to boson mass reconstruction in the four-jet final states, which improves both width and shape of the Higgs boson mass distribution. In addition, the results are shown of the dedicated machine learning implementations for background rejection in dijet and four-jet final states analyses of higgsstrahlung process at sqrt(s) = 240 GeV.

Speaker: Dr Marina Chadeeva (LPI, Moscow)

16:50 Toward a Measurement of the Higgs Boson Mass with Natural-Width Precision at future e+e- colliders

N/A

Speaker: Jan Eysermans

17:15 Precision Study of Type-II 2HDM at the lepton colliders

We combine the latest experimental data to investigate the potential of future precision measurements at the CEPC to probe new physics beyond the Standard Model, focusing on the Type-II two Higgs doublet model (Type-II 2HDM). The contributions from the heavy Higgs bosons at both the tree level and the one-loop level are included over the full parameter space. We perform a multiple variable global fit and study the extent to which the parameters of non-alignment limit and non-degenerate masses can be probed by the precision measurements. We find that future Higgs precision measurements can significantly constrain the allowed parameter space of the Type-II 2HDM, especially for small and large values of $\tan\beta$. The precision measurements at the Z-pole and at the Higgs factory are highly complementary in constraining the mass splittings among the heavy Higgs bosons and can provide indirect constraints on their masses. The typical results are $|\cos(\beta-\alpha)| < 0.0038, |\Delta m_\Phi | < 100$ GeV.

Speaker: 菊香 李 (Sun Yat-Sen (Zhongshan) University)

17:40 Probing strong first-order electroweak phase transition scenarios in two-Higgs-doublet model with FCC-ee/CEPC

N/A

Speaker: Anisha Anisha

16:00 → 18:00 Silicon Detectors: 2

Zoom Link, ID: 91011235165, Code: 983836

19:00 → 21:00 Reception

Friday, 23 October

09:00 → 10:40 Accelerator: 3

Zoom Link, ID: 94805716496, Code: 217749

09:00 Status of e+e- colliders in BINP

Speaker: Anton V. Bogomyagkov

09:20 CEPC Vacuum system production line EDR status

Speaker: Yongsheng Ma

09:40 CEPC Survey and Mechanical system status

Speaker: Haijing Wang

10:00 CEPC alignment and installation EDR status

Speaker: Xiaolong Wang

10:20 CEPC machine protection with collimators and transport line systems EDR status

Speaker: Xiaohao Cui

09:00 → 10:30 CIPC & Industrial Partnerships: 3

Zoom Link, ID: 934 7906 6977, Code: 522727

09:00 → 10:35 Higgs Physics: 3

Zoom Link, ID:99229612134, Code: 887914

Convener: Shuo Han (IHEP (高能所))

09:00 Discovery Prospects for the 95 GeV Higgs Candidate at CEPC

N/A

Speaker: Bruce Mellado (IHEP)

09:25 Probing the Electron Yukawa Coupling through Polarized e⁺e⁻ → H → gg Production at the CEPC

The electron Yukawa coupling has not yet been directly tested at the strength predicted by the Standard Model. An electron–positron collider operating at the Higgs pole can probe this coupling through resonant s-channel Higgs production, although the tiny signal rate and large continuum backgrounds make the measurement exceptionally challenging.
We investigate e⁺e⁻ → H → gg in a conditional CEPC scenario with 10 ab⁻¹ and oppositely directed transverse polarizations of 70% for both beams. Events are processed using a CEPC Delphes-based fast detector simulation with a gluon-tagging response informed by CEPC full-simulation studies. An event-level Particle Transformer is combined with a two-dimensional binned likelihood fit to the classifier score and event azimuthal angle.
With the CEPC full-simulation-informed tagging response, the statistical-only fit gives an expected local significance of 0.2 sigma against the e⁺e⁻ → q q̄ background. A separate configuration adopting the idealized tagging assumptions used by d’Enterria and collaborators in their FCC-ee study reaches 4.5 sigma.

Speaker: siya feng (中科院高能物理研究所)

09:50 Higher-order calculations for Higgs physics at future e+e- colliders

N/A

Speaker: Jian Wang (Shandong University)

10:15 Heavy Jet Mass in Hadronic Higgs Decays

N/A

Speakers: Xiaoyuan Zhang, Xiaoyuan Zhang (Harvard University)

09:00 → 10:30 Silicon Detectors: 3

Zoom Link, ID: 91011235165, Code: 983836

10:30 → 11:00 Coffee break

11:00 → 12:30 Accelerator: 4

Zoom Link, ID: 94805716496, Code: 217749

11:00 SRF activites in Korea

Speaker: Yeonsei Chung

11:20 Post-processing of CEPC SC cavities: review and outlook for mass production

Speaker: Song Jin

11:40 CEPC accelerator instrumentation EDR status

Speaker: Yanfeng Sui

11:00 → 12:30 Calorimetry: 1

Zoom Link, ID: 91011235165, Code: 983836

11:00 → 12:40 Physics Beyond SM: 1

Friday Morning: Function Room 11
Zoom Link, ID: 934 7906 6977, Code: 522727

Friday Afternoon and Saturday Morning: Junior Ballroom I
Zoom Link, ID:99229612134, Code: 887914

11:00 Probing the Electroweak Phase Transition with Long-Lived Scalars at Future Lepton Colliders

A strong first-order electroweak phase transition (EWPT) can be realized through the introduction of a light scalar that is weakly coupled to the Higgs boson. Such weak couplings can result in a macroscopic lifetime, leading to displaced decays that provide a distinctive experimental signature. In this talk, we investigate the sensitivity of future lepton colliders to long-lived scalars "s" produced in Higgs decays through e^+e^- -> ZH, with H -> ss and the scalars decaying at displaced vertices. Using realistic detector simulation, we develop a selection-based analysis and explore machine learning methods using detector level information to further improve the sensitivity. Our results demonstrate the potential of long-lived particle searches at future lepton colliders to provide a new probe of EWPT physics.

Speaker: Xiang Chen (Shanghai Jiao Tong University)

11:20 Scalar Portals to Dark Matter

The search for dark matter at accelerators has a long history, dating back to the first proposals for the LHC and even earlier. While complementary to direct detection in certain respects, accelerator-based searches offer distinct advantages, particularly when investigating a complex dark sector and multi-step processes. As a precision machine with unique potential, the planned CEPC accelerator is capable of covering regions of the parameter space of new physics models that remained beyond the sensitivity reach of the LHC. In the talk we discuss a range of scalar portal models that are of interest for study at the CEPC, taking into account existing constraints from the LHC.

Speaker: Maria Savina (JINR)

11:40 The 152 GeV Candidate: Status Update and Implications for the CEPC

A number of excesses observed in LHC data have motivated the hypothesis of a new Higgs-like scalar with a mass near 152 GeV. This presentation will begin with a brief introduction to the history of the 152 GeV candidate, from the multi-lepton anomalies and the prediction of a scalar mass near 150 GeV to the subsequent excesses observed in the \gamma\gamma, Z\gamma, and WW channels.

The main focus will be an update on the current status of the 152 GeV candidate and recent phenomenological developments. In particular, excesses in the \ell\ell\gamma final state were predicted as part of the emerging phenomenological framework, and recent studies of LHC data now reveal excesses consistent with these predictions. The presentation will also discuss recent studies of the \gamma\gamma jj final state and how these results contribute to the developing picture of the 152 GeV candidate.

Finally, recent results on the implications for the CEPC will be presented. Explaining the pattern of excesses observed at the LHC requires an extension of the scalar sector that, in addition to the neutral scalar near 152 GeV, contains a charged scalar state. The existence of this charged scalar is therefore a prediction of the framework used to account for the LHC data. Its discovery is extremely challenging at the LHC because of the large associated backgrounds, whereas the clean experimental environment of the CEPC provides a unique opportunity to discover this charged component. The CEPC can therefore play a decisive role by directly probing a key prediction of the scalar-sector extension associated with the 152 GeV candidate.

Speaker: Bruce Mellado (IHEP)

12:00 Probe Axion-Like Particles and Tau Weak Electric Dipole Moments at Future Lepton Colliders

Speaker: Keping (可平) Xie (谢) (Tsung-Dao Lee Institute, Shanghai Jiao Tong University)

11:00 → 12:30 QCD: 1

Zoom Link, ID:99229612134, Code: 887914

11:00 Stable NNLO QCD Predictions for Quarkonium Production and Decay

Heavy quarkonia provide ideal probes of strong interactions in both the perturbative and nonperturbative regimes. They have therefore been extensively studied at a wide range of accelerator-based high-energy experiments, including electron-positron colliders such as BESIII, Belle, and LEP, as well as at future facilities. However, NNLO QCD predictions for quarkonium production and decay processes are known to suffer from perturbative instabilities. We identify the origin of this instability and propose a remedy that significantly improves the perturbative stability of the NNLO predictions and the agreement between theory and data.

Reference: https://arxiv.org/abs/2606.28494

Speaker: Guoxing Wang (LPTHE, CNRS, France)

11:22 The Four-Jet Production in Electron-Positron Annihilation at Order alpha_s^4

In this talk, I will present the calculation of next-to-next-to-leading-order (NNLO) correction to four-jet production in electron–positron annihilation. We for the first time predicated present precise phenomenological predictions for the four-jet rate. I will then present NNLO predictions for several four-jet event-shape distributions and investigate the corresponding hadronisation effects.

Speaker: Huiting Sun (山东大学物理学院)

11:44 Complete angular analysis of polarized top-quark decay at NNLO in QCD with a finite bottom-quark mass

We present the next-to-next-to-leading-order (NNLO) QCD corrections to the
angular distribution of the polarized top-quark decay
$t(\uparrow)\to W^+X_b$, followed by $W^+\to\ell^+\nu_\ell$, with an on-shell
$W$ boson. We compute eight helicity structure functions, comprising
three spin-independent and five spin-dependent functions, through
$\mathcal{O}(\alpha_s^2)$, both in the massless-bottom approximation and with
the bottom-quark mass retained. These results extend the complete
next-to-leading-order angular analysis to NNLO and provide consistent
predictions for the total decay width, the $W$-boson helicity fractions,
polar-angle asymmetries, azimuthal correlations, and the elements of the
top--$W$ double density matrix.

Speaker: 国富 徐 (山东大学物理学院)

12:06 Measurement of $\Xi^{-} / \bar{\Xi}^{+}$ production in jets from Z boson decays with the DELPHI open data

This presentation reports the studies of the $\Xi^{-} / \bar{\Xi}^{+}$ baryon production in energy-ranked jets produced in $Z\to\text{hadrons}$ decays using the DELPHI open data. Jets are reconstructed using the Durham algorithm with $y_{\text{cut}}=0.005$. Quark- and gluon-enriched jet samples are obtained by ranking the jet energies in three-jet events. The softest jets are found to produce fewer $\Xi^{-}/\bar{\Xi}^{+}$ and less energetic baryons than the other jets. The ratio of $\Xi^{-}/\bar{\Xi}^{+}$ production rates in gluon and quark jets, each normalized to the corresponding mean charged-particle multiplicity, is measured. The result is consistent with the JETSET expectation and the OPAL measurements of $K_S^0$ and $\Lambda$ productions in $Z$ decays. Preliminary investigation of $\Lambda\bar\Lambda$ pair production is also presented. These studies provide new insights into strange-quark production and hadronization. Future $e^{+}e^{-}$ colliders such as CEPC and FCCee will provide much larger $Z$-boson samples and will allow far more precise studies of the subject.

Speaker: Dr Yuzhi Che (IHEP)

12:30 → 14:00 Lunch break

14:00 → 15:30 Accelerator: 5

Zoom Link, ID: 94805716496, Code: 217749

14:00 CEPC RF power sources and power distribution EDR status

Speaker: Zusheng Zhou

14:20 CEPC collider ring permanent quadrupole magnet development status

Speaker: Chuang Shen

14:40 The status of CEPC accelerator design program kit: APES

Speakers: Tianmu Xin, Yuan Zhang

15:00 AI accelerator application activities at IHEP

Speaker: Jinyu Wan

14:00 → 15:30 Calorimetry: 2

Zoom Link, ID: 91011235165, Code: 983836

14:00 → 15:30 QCD: 2

Zoom Link, ID:99229612134, Code: 887914

14:00 Tracing QCD Vacuum Fluctuations during Hadronization with Conserved Currents

We propose the first moments of electric-charge, baryon-number, and strangeness flows into jets as direct probes of the flavor composition and diquark content of the QCD vacuum excitations during hadronization. Current conservation laws render these moments invariant under renormalization-group evolution, while color triality constrains the allowed screening states at the endpoint of the associated Wilson line. In a minimal screening picture, the baryon-number flow in a quark jet of flavor $f$ obeys $\langle B_{\rm flow}\rangle_f \simeq r_{qq}/(1+r_{qq})$, where $r_{qq}$ is the relative production weight of diquark--antidiquark and quark--antiquark vacuum excitations. If the pair-production weights among different flavors satisfy $u\bar u:d\bar d:s\bar s=1:1:r_s$, the strangeness flow obeys $\langle S_{\rm flow}\rangle_f \simeq S_f+\frac{3r_s}{2+r_s}\left(\frac{1}{3}-\langle B_{\rm flow}\rangle_f\right)$, predicting a nonzero net strangeness even in $u$- and $d$-initiated jets. The charge flow obeys an analogous relation, and isospin-symmetric pair production makes the three flows satisfy the Gell-Mann--Nishijima relation $\langle Q_{\rm flow}\rangle_f \simeq I_{3,f} +\frac{1}{2}\left(\langle B_{\rm flow}\rangle_f+\langle S_{\rm flow}\rangle_f\right)$, providing an internal consistency condition among the three observables. Event-generator studies reproduce these relations and demonstrate that joint measurements of $Q$, $B$, and $S$ can separately constrain $r_{qq}$ and $r_s$, providing a flavor-resolved probe of vacuum pair production and quantum-number transport during jet hadronization.

Speaker: Wanchen Li (Fudan University)

14:22 Resolving the Light-Flavor Composition of Hadronic Z Decays with DELPHI Open Data

We report a direct determination of the strange-quark fraction in hadronic Z decays using DELPHI open data. A five-flavor ParticleNet representation defines exclusive flavor-enriched and remainder counts, while an independent data/simulation sample constrains the flavor response and its associated uncertainties. A simultaneous fit with freely floating bottom and charm fractions separates the strange contribution from the complementary (u+d) component without imposing (Rd = Rs), allowing the light-flavor composition to be determined directly from the flavor-tagged event yields. The heavy-flavor results agree with established LEP measurements, providing a consistency check on the flavor separation. The analysis demonstrates how modern flavor-tagging techniques can be applied to archival LEP data to revisit the flavor structure of hadronic Z decays and precision studies of light-quark production in QCD. Response calibration, rather than counting statistics, limits the precision.

Speaker: Shuo Han (IHEP (高能所))

14:44 Dihadron Fragmentation as a Spin Analyzer at Lepton Colliders

Spin-dependent dihadron fragmentation provides a unique way to access the polarization and spin correlations of light quarks and gluons at lepton colliders. In this talk, I will discuss how dihadron fragmentation can serve as a spin analyzer and be used to study a range of phenomena, including Bell inequality violation, anomalous electromagnetic dipole interactions, light-quark Yukawa couplings, and the color-octet mechanism in bottomonium decays. I will also show how the same framework can be extended from quark transverse spin to gluon linear polarization. These studies demonstrate that dihadron fragmentation offers a versatile probe of otherwise inaccessible partonic spin information and its underlying dynamics.

Speaker: Prof. Bin Yan (IHEP)

15:06 Leaves-to-Tree: Deep-Learning Reconstruction of K_S^0 and Λ from Charged Tracks at CEPC

Identified light-hadron production in Z→qq̄ events — K_S^0, Λ, φ, K⁰ and ρ⁰ — is sensitive to quark fragmentation, strangeness suppression and vector-meson production, and its precision at CEPC is limited by the reconstruction of the corresponding two-body decays from charged tracks. This contribution presents a deep-learning implementation of the "leaves-to-tree" step at CEPC: neutral hadrons are reconstructed directly from charged tracks using ParT. Focusing on the benchmark channels K_S^0→π⁺π⁻ and Λ→pπ⁻, the reconstruction efficiency, the purity and their product are compared with the conventional cut-based reconstruction, both integrated and as a function of the reconstructed energy. Extensions to the prompt resonances φ, K⁰ and ρ⁰ and to multi-body decays, and the prospects for precision measurements of identified-hadron production at the Z pole, are also discussed.

Speaker: 嵩 潘 (上海交通大学)

14:00 → 15:30 Sustainability in HEP: 1

Friday Afternoon: Function Room 11
Zoom Link, ID: 934 7906 6977, Code: 522727

Monday Morning: Junior Ballroom I
Zoom Link, ID:99229612134, Code: 887914

15:30 → 16:00 Coffee break

16:00 → 18:00 AI & Machine Learning in HEP: 1

Zoom Link, ID: 934 7906 6977, Code: 522727

16:00 Optimal Binning from Optical Binning: a Machine Learning Approach

We will describe progress along simulation based inference in the precision era.

Speaker: Lingfeng Li (Brown University)

16:20 AI for High Energy Phenomenology — What’s next?

Artificial intelligence has rapidly become an integral part of high-energy physics, evolving from specialized machine-learning tools for individual analysis tasks toward increasingly general and large-scale models for scientific data. As this field enters a new stage, an important question is not only how to build more powerful models, but also what we can learn from the models themselves. In this talk, I will review recent developments in AI for high-energy phenomenology, with a particular focus on collider physics and the emerging paradigm of foundation models. I will then discuss ongoing efforts to probe the internal representations learned by these models, using geometric approaches to study how their representations evolve during training and across architectures. More broadly, I will argue for a perspective on Scientific AI in which AI is not merely a computational tool for solving predefined physics tasks, but can increasingly serve as a new instrument for uncovering physical structures from the data itself.

Speaker: 恬吉 蔡 (同济大学)

16:40 AI scientist for LQCD: a new tools at CEPE

This talk introduces LQCDMaster, an AI agent framework that turns natural-language physics requests into executable lattice QCD workflows. Combining physics planning, PyQUDA code generation, automated debugging, and GPU execution, it supports a range of hadronic observables. We present its architecture and assess its reliability through numerical validation against expert-written reference programs.

Speaker: Wei Wang (SJTU)

17:00 Agentic AI and Deep Learning at BESIII

This talk provides an overview of recent advances in agentic AI and deep learning at BESIII. I will introduce DrSai, a multi-agent system designed for autonomous end-to-end physics analysis—from natural-language goals to data selection, statistical inference, and systematic evaluation—with emphasis on reliability, traceability, and human-AI collaboration. I will also overview our deep-learning efforts, including an experimental-data foundation model, SAM-based reconstruction of intermediate resonances, and machine-learning-based beam-background suppression in the BESIII trigger. Finally, I will discuss the evolving role of AI—from an efficiency tool to an active reasoning partner in scientific discovery—and how human-AI collaboration can accelerate high-energy physics and beyond.

Speaker: Dr Ke LI (IHEP)

17:20 Agentic AI for Particle-Physics Detector Operations: Towards an AI-Assisted Shifter

Modern particle-physics detectors require continuous monitoring, rapid anomaly detection, and timely expert response. This contribution presents an Agentic AI framework for intelligent detector operations, integrating sensor information, automated anomaly detection, contextual interpretation, and decision support.
Environmental and operational sensor data are analysed using Agentic AI tools that generate alerts, interpret detector conditions, and provide recommendations to experts and shifters. The framework is also being extended to Data Quality Monitoring through autoencoders applied to detector monitoring histograms.
Agentic AI is used to interpret anomalies in context, correlate information from multiple monitoring sources, and recommend possible actions. This approach represents a step towards an AI-assisted shifter and provides a pathway to intelligent monitoring for current and future high-energy physics facilities.

Speaker: Bruce Mellado (IHEP)

17:40 A Human-Governed Agentic Workflow for HEP Analysis: Design, Skills, and Evaluation

Recent coding agents can execute increasingly complex scientific workflows, but realistic high-energy physics (HEP) analyses remain nonlinear and require domain expertise, systematic validation, reproducible evidence, and human scientific judgment. We present a human-governed, skill-oriented workflow for agent-assisted HEP analysis. Native coding agents perform planning, coding, computation, validation, and documentation, while reusable Skills provide HEP-specific methods and checks on demand. Rather than imposing a dedicated orchestrator or fixed workflow graph, the approach builds on native agent capabilities and composes Skills according to the task and its risks. Human researchers retain scientific authority and review versioned evidence and analysis packages through GitLab. We demonstrate the workflow through a joint measurement of Rb, Rc, and Rs using LEP Open Data, and introduce evaluations ranging from Skill activation tests to blinded full-analysis benchmarks derived from real analysis history. These studies explore how agent autonomy, domain knowledge, and human oversight can be combined for reliable and reproducible HEP analysis.

Speaker: Shuo Han (IHEP (高能所))

16:00 → 18:00 Accelerator: 6

Zoom Link, ID: 94805716496, Code: 217749

16:00 Status of HALHF

Speaker: Brian Foster

16:20 Status of EuPRAXIA at INFN and its possible synergies with the CEPC/FCCee

Speaker: Massimo Ferrario

16:40 On plasma accelerator activities in Beijing University

Speaker: Xueqing Yan

17:00 IHEP plasma accelerator test facility status

Speaker: Dazhang Li

17:20 Plasma acceleration software development and different plasma injection schemes

Speaker: Ming Zeng

17:40 Plasma electron positron linear collider perspectives

Speaker: Shiyu Zhou

16:00 → 18:00 Calorimetry: 3

Zoom Link, ID: 91011235165, Code: 983836

16:00 → 18:00 Physics Beyond SM: 2

Friday Morning: Function Room 11
Zoom Link, ID: 934 7906 6977, Code: 522727

Friday Afternoon and Saturday Morning: Junior Ballroom I
Zoom Link, ID:99229612134, Code: 887914

16:00 Probing the Real Triplet Higgs Model with Higgsstrahlung at future $e^+e^-$ colliders

Speakers: CRISTIAN SIERRA (上海交通大学), Cristian Sierra (TDLI)

16:20 2HDMs with extended U (1) gauge symmetry at current and future colliders

Speakers: Xinran XU (The Hong Kong University of Science and Technology), Xinran Xu (hkust)

16:40 H-COUP developments

Speaker: kodai sakurai

17:00 An opportunity to measure Bf (Z→ nu_e nu_e_bar) with a high accuracy at CEPC

Speakers: Alexey Drutskoy (LPI), Alexey Drutskoy (LPI)

17:20 Testing Bell inequalities and probing quantum entanglement at CEPC

Speaker: Alim Ruzi (school of physics Peking Uniersity)

19:20 → 21:35 Plenary: Public Lecture

Thursday Morning: Grand Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

Monday Afternoon: Junior Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

19:30 质量的奥秘 （一）

Speaker: Liantao Wang (University of Chicago)

20:10 质量的奥秘（二）

Speaker: Yifang Wang (高能所)

Saturday, 24 October

09:00 → 10:40 Accelerator: 7

Zoom Link, ID: 94805716496, Code: 217749

09:00 On accelerator activities in Korea G4 light source

Speaker: Seunghwan Shin

09:20 Operation experiences of BEPCII U and HEPS

Speaker: Daheng Ji

09:40 CEPC control system EDR status

Speaker: Dapeng Jin

10:00 CEPC powers sources in EDR

Speaker: Bin Chen

10:20 CEPC injection and extraction hardware in EDR

Speaker: Jinhui Chen

09:00 → 10:30 MDI, Mechanics & Integration: 1

Saturday Morning: Junior Ballroom III
Zoom Link, ID: 91011235165, Code: 983836

Saturday Afternoon: Function Room 10
Zoom Link, ID: 94805716496, Code: 217749

09:00 CEPC Interaction Region engineering design status of MDI

Speaker: Haijing Wang (高能所)

09:18 CEPC SCQ cryostat design

Speakers: 啸辰 杨 (高能所), 张祥镇 ZHANG Xiangzhen (高能所)

09:36 LumiCal for luminosity and precision test of QED

Purpose: Small-angle Bhabha scattering of e+e- → e+e-(nγ) has a very large cross-section and is a favorable process for measuring e+e- collision luminosity. The theoretical precision is approaching 10-4. The experimental measurements of radiative Bhabha interactions have been achieved at the 1 % level. We present Monte Carlo simulations using BHLUMI and BHWIDE programs to estimate the detection of radiative photons for higher-order contributions.

Methods: Future collider projects are proposed for flavor facilities and Higgs factories of the FCC-ee and the CEPC. Luminosity detectors are proposed as precision luminometers for detection of the well-predicted Bhabha scattering events. The LumiCal is designed within the Machine-Detector Interface (MDI) region on both sides of the Interaction Point surrounding the beam-pipe before the quadrupole magnets. Bhabha scattering events are simulated for center-of-mass energies of 91 to 360 GeV for Higgs factories. The Bhabha cross-sections and the distributions of radiative photons are compared.

Results: Radiative photons are generated with the Yennie–Frautschi–Suura (YFS) exclusive exponentiation method. The event rates of photons with energies near zero are compatible independent of the electron energies. Photons are populated surrounding the incident or scattered electrons. The e/gamma identification is conducted with silicon sensors to detect electrons and LYSO arrays for shower clusters of electrons and photons. The segmentation of LYSO arrays separating shower clusters can distinguish e/gamma with an opening angle of more than 2 cells (~10 mrad). The photon event rates and angular distributions can be measured for higher-order terms in QED.

Conclusion:
The exclusive measurement of radiative photons in Bhabha events. The goal is for 10-4 precision on Bhabha event counting at future collider projects.

Speaker: Suen Hou (IPAS)

09:54 EMD in integrated luminosity measurement at the Z-pole

In order to ensure measurement of the integrated luminosity with a relative precision of 10−4 at the Z0 pole at CEPC, numerous systematic effects have to be quantified and corrected for. Here we discuss collective impact of electromagnetic bunch fields on the initial state electrons and positrons as well as on the final states produced in Bhabha scattering. These effects change four-momenta of the final state particles, leading to modification of Bhabha count in the instrumented volume. Size of the counting loss is quantified in simulation, and experimental method based on machine learning is discussed in order to correct for this loss.

Speaker: Ivanka Bozovic (Vinca Institute of Nuclear Sciences)

10:12 Development of 4H-SiC Low-Gain Avalanche Diode (SICAR3) for the CEPC Fast Luminosity Detector

The Circular Electron Positron Collider (CEPC) requires a fast luminosity detector to achieve a relative measurement precision of 2% at a sampling rate of 1 kHz in order to drive a real-time orbit feedback system, due to its extremely high luminosity. 4H-SiC, with its wide bandgap, high displacement threshold energy, and high saturated electron drift velocity, simultaneously offers excellent radiation hardness (particularly its superior tolerance to gamma rays), picosecond-level time response, and low leakage current at elevated temperatures. These properties make it perfectly suited for the extreme environmental demands of fast luminosity detection in the forward region of CEPC.

This work reports on the development progress of the 4H-SiC Low-Gain Avalanche Diode (SICAR3). The device fabrication is based on a mature 350 nm MOSFET process platform. The SICAR3 achieves an avalanche gain of 10–15 and a time resolution improved to 60 ps. In terms of key design, the device directly adopts a high-temperature ion-implanted Junction Termination Extension (JTE) as the termination structure, which effectively suppresses leakage current and overcomes the limitation on the usable active area. The successful tape-out of SICAR3 lays a solid foundation for the engineering application of large-area, low-leakage 4H-SiC LGADs for the CEPC fast luminosity detector.

Speaker: Xiyuan 希 媛 Zhang 张

09:00 → 10:40 Offline Computing & Software: 1

Zoom Link, ID: 934 7906 6977, Code: 522727

09:00 The current status of core software for CEPC

This contribution reports the current status and recent progress of the CEPC core software, emphasizing its architecture, key components, and development workflow. The framework combines modern C++ and Python toolchains with a modular reconstruction chain and a unified geometry and conditions data model for long-term stability and reproducibility. We describe the continuous-integration and validation strategy, the versioned release process, and an automated performance-validation system that uses Kafka to orchestrate and execute validation steps. We also summarize recent developments, including simulation with the Gaussino framework, Diffusion Transformer (DiT)-based fast-simulation interfaces, reconstruction performance optimizations, and expanded analysis toolkits.

Speaker: Tao LIN (高能所)

09:20 Simulation and Reconstruction for the Highly Granular Scintillating-Glass Calorimeter in the AGORA Detector

A highly granular scintillating-glass calorimeter is being developed for the AGORA detector concept, motivating dedicated software developments for detector simulation and event reconstruction. The detector geometry has been implemented in the CEPC software framework (CEPCSW) based on DD4hep, enabling Geant4 simulation and performance studies with EDM4hep-based event data.

This contribution presents the current software development for the scintillating-glass calorimeter, covering detector implementation, simulation, digitization, and reconstruction. A detector-response model is being developed to bridge Geant4 energy deposits and realistic calorimeter signals, including scintillation light generation, optical photon transport, light collection efficiency, SiPM response, and related detector effects.

In parallel, the CyberPFA particle-flow reconstruction algorithm is being adapted to the highly granular scintillating-glass geometry. Ongoing developments include clustering, energy-core based shower recognition, and photon reconstruction, with the ultimate goal of achieving full particle-flow and jet reconstruction for the scintillating-glass calorimeter within CEPCSW.

Speaker: Dr Yang Zhang

09:40 DiT-based fast simulation for the CEPC long-bar crystal electromagnetic calorimeter

The CEPC is a proposed high luminosity e+e− collider designed for precision measurements of the Higgs, W, and Z bosons. Its reference detector incorporates a long bar crystal ECAL, which employs long, narrow crystal bars arranged in orthogonal layers to deliver fine 3D shower imaging and excellent compatibility with Particle Flow reconstruction. [1]

For CEPC physics analyses, large volumes of simulated data are essential. Calorimeter simulation is by far the most CPU intensive component of the CEPC detector simulation, accounting for roughly 80% of the total simulation budget. Consequently, the development of fast simulation techniques is a critical R&D priority.

Our work is inspired by CERN’s CaloDiT-2 [2], which develops a fast simulation framework based on the Diffusion Transformer (DiT). Our implementation, named Voxel Diffusion Transformer for Calorimeter (VoDiT4CAL), is built using PyTorch [3] and Lightning [4]. Building on the design principles of CaloDiT-2, VoDiT4CAL introduces two key enhancements:

Enhanced Local Spatial Modelling: VoDiT4CAL incorporates PixelDiT [5] layer to better capture local spatial correlations, which reduces the DiT depth and significantly lowers computational cost.
Enhanced Energy Modelling: VoDiT4CAL adds energy prediction head and dynamically redistributes energy across voxels.
Testing shows that VoDiT4CAL accurately reproduces key photon shower distributions across incident energies from 0.25 GeV to 100 GeV, meeting CEPC physics precision requirements. This contribution also presents a detailed report on distillation(for accelerating inference [6]), its impact on physics performance, and the practical speedup achieved after integrating VoDiT4CAL into the official CEPC software framework.

[1] Souvik Priyam Adhya et al. “CEPC Technical Design Report - Reference Detector”. In: (Oct. 2025). arXiv: 2510.05260 [hep-ex].
[2] Piyush Raikwar et al. “A Generalisable Generative Model for Multi-Detector Calorimeter Simulation”. In: (Sept. 2025). arXiv: 2509.
07700 [physics.ins-det].
[3] Adam Paszke et al. “PyTorch: An Imperative Style, High-Performance Deep Learning Library”. In: Advances in Neural Information
Processing Systems 32. Curran Associates, Inc., 2019, pp. 8024–8035. URL: http://papers.neurips.cc/paper/9015-pytorch-
an-imperative-style-high-performance-deep-learning-library.pdf.
[4] William Falcon and the PyTorch Lightning team. PyTorch Lightning. 2024. DOI: 10.5281/zenodo.13254264. URL: https://doi.
org/10.5281/zenodo.13254264.
[5] Yongsheng Yu et al. “PixelDiT: Pixel Diffusion Transformers for Image Generation”. In: arXiv preprint arXiv:2511.20645 (2025).
[6] Kaiwen Zheng et al. “Large Scale Diffusion Distillation via Score-Regularized Continuous-Time Consistency”. In: ArXiv abs/2510.08431
(2025). URL: https://api.semanticscholar.org/CorpusID:281950486.

Speaker: Zhihao Li (IHEP)

10:00 CEPC TPC Track Finding: A GNN-DBSCAN Pipeline and LLM-Agent Autonomous Search

The CEPC tracker relies on a high-granularity Time Projection Chamber (TPC) to provide precise track reconstruction and particle identification. Traditional reconstruction relies on signals digitized using pad-like methods, which fails to utilize the full signal features during track reconstruction. To more accurately explore the true capabilities of pixel-readout TPCs, we incorporated realistic ionization and drift-diffusion effects into the simulation and digitization processes to obtain comprehensive signals analogous to real data as inputs for track reconstruction. We adapt a multi-stage tracking method originally developed for MDC tracking and apply it to CEPC TPC track finding. The pipeline first uses a graph neural network (GNN) to suppress noise hits. DBSCAN is then applied to the GNN-filtered hits to cluster primary track hits. Finally, RANSAC fitting is used to complement the DBSCAN results, which specially retrieves missed, broken, and poorly clustered tracks that cannot be identified by density-based clustering. In parallel, we adopt the AIDE intelligent agent framework to autonomously search, design, iterate and optimize track finding models for CEPC TPC. The search space covers supervised, unsupervised, and deep-learning strategies, and every candidate is quantitatively evaluated with customized tracking metrics, including hit clustering efficiency, hit clustering purity, and track reconstruction efficiency. Preliminary simulation results on CEPC qqH Monte Carlo samples show that both the GNN-clustering pipeline and the agent-optimized models provide promising TPC track reconstruction performance.

Finally, we outline future optimization plans for CEPC TPC tracking, including improving track finding efficiency and suppressing fake track rates, optimizing the reconstruction of low-momentum tracks, and joint reconstruction with silicon detectors. These efforts aim to further enhance tracking performance for future CEPC physics analyses.

Speaker: Dr 晓倩 贾 (IHEP)

10:20 Improving Tracking Performance with Cluster Counting in Drift Chambers

Future e⁺e⁻ collider experiments place stringent performance demands on their detectors. As a foundation of particle physics measurements, the tracking system must not only reconstruct particle trajectories but also deliver high-precision momentum determination. A drift chamber equipped with cluster counting can significantly enhance particle identification; moreover, the recorded high-precision waveforms provide individual electron arrival times, offering the potential to surpass conventional position resolution and thereby substantially improve momentum resolution.

Conventional waveform processing in drift chambers typically records only the time at which the signal crosses a threshold and estimates the distance of closest approach (DOCA) via an x−t relation, making the measurement sensitive to ionization fluctuations and electron diffusion. In contrast, drift chambers utilizing cluster counting employ high-bandwidth, high-sampling-rate readout electronics that capture complete waveforms, making it possible, in principle, to extract the arrival time of each drift electron. While this approach opens the door to high-precision DOCA measurements, it also introduces significant complexities in inferring the DOCA from these arrival times, posing a significant challenge for reconstruction algorithms.

In this study, we develop a Transformer-based method with attention pooling to exploit the multiple electron arrival times extracted from the full waveform in the CEPC drift chamber. Simulation results demonstrate improvements of 27.2% in hit-position resolution and 45.0% in momentum resolution relative to conventional DOCA estimation using the x−t relation. This work lays the essential groundwork for high-precision waveform processing and track reconstruction at future colliders.

Speaker: Yiqi DU (Wuhan University)

09:00 → 10:40 Physics Beyond SM: 3

Friday Morning: Function Room 11
Zoom Link, ID: 934 7906 6977, Code: 522727

Friday Afternoon and Saturday Morning: Junior Ballroom I
Zoom Link, ID:99229612134, Code: 887914

09:00 Searching for dark photons from dark-scalar decays at CEPC and FCC-ee

Speakers: Zeren Simon (泽人) Wang (王) (Hefei University of Technology), Zeren Simon Wang (University of Bonn)

09:20 Quantum information of photon pairs at lepton colliders

Speaker: Prof. Bin Yan (IHEP)

09:40 Tera-Z as a discovery machine

Speaker: Juraj Klaric

10:00 Optimisation of the vertex detector and measurement of Higgs decays to second-generation quarks at the CEPC

Speaker: 家琳 李 (上海交通大学)

10:30 → 11:00 Coffee break

11:00 → 12:40 Accelerator: 8

Zoom Link, ID: 94805716496, Code: 217749

11:00 Highlights of the TTC2026

Speaker: Carlo Pagani

11:20 CEPC SRF (both collider & booster) EDR status

Speaker: Rui Ge / Song Jin

11:40 CEPC cryogenic system EDR status

Speaker: Mei Li / Rui Ge

12:00 CEPC IR SC sextupole cryostat design

Speaker: Ruixiong Han

12:20 CEPC SC quadrupoles and sextupole development in EDR and status

Speaker: Yingshun Zhu

11:00 → 12:30 Electronics & Readout Systems: 1

Zoom Link, ID: 934 7906 6977, Code: 522727

11:00 Design and Test Results of the SIPAC: A Prototype SiPM Readout ASIC for CEPC Calorimeters

Speaker: Huaishen LI (IHEP)

11:18 Serial Powering for the Front-End Electronics

The pixel density of the front-end detectors continues to rise, and with it the power they consume—now stretching into the watt range—while the cable mass and thermal budget of the detector volume remain essentially fixed. Today's arrays are powered in parallel at low voltage and high current (roughly 2 V/24 A), a scheme that already strains the cable budget and the associated I²R losses. This work moves to serial (constant-current) powering: a single input of 48 V/1 A uses high voltage and low current to cut cable losses, which is especially attractive in the strong solenoid field and under a strict noise budget. Serial powering removes the cable problem but brings its own set of challenges: shunt-branch dissipation, an uncontrolled open circuit that can take down the whole chain, a floating local ground with no shared reference, and added noise. These are precisely the difficulties already encountered in the ATLAS serial-powering schemes.
Candidate conversion topologies are reviewed and compared: buck DC-DC, switched-capacitor, shunt LDO, and hybrid combinations. A buck is efficient at a small step-down ratio, but its switching-node parasitics grow as the ratio increases, and magnetic-core inductors do not survive the field; small air-core parts remain a workable fallback. Switched-capacitor converters are compact and fixed-ratio, but they are inefficient at large conversion ratios and need many capacitors and high switching frequencies. Two hybrid approaches are proposed. The first is a delta-modulated switched-capacitor stage followed by an LDO: it needs no inductor, operates in series, and reaches about 80% efficiency at roughly 500 µV ripple, though redundancy and the LDO dropout limit its transient response. Replacing that stage by a switching constant-current capacitor, a hybrid buck, and an ultra-low-dropout LDO requires only a small air-core inductor (~0.5–1 µH), reaches above 90% at about 100 µV ripple, and trades current margin for voltage margin, giving good short-burst response without sacrificing efficiency.
A 1.1 A four-stage simulation, with 1.8 V and 1 A per stage and a 60 dB LDO gain, is used to model the rail build-up, constant-current capacitor charging, and final LDO settling. Two demo boards confirm the concept in hardware, including a version built around an 80 V/10 A GaN power stage, a 1 MHz buck with an 8 A NMOS, and a 1.5 A LDO with 150 mV dropout. Results show a stable serial chain settling to a 3.3 V rail and successful cascaded charging.
Three key issues specific to serial powering are addressed. Because the reference ground floats along the chain, the HV MAPS substrate, which must be back-biased to −70 V to fully deplete the bulk (versus about −6 V in conventional MAPS), requires each die to generate its own independent bias voltage for collection efficiency; the simulation confirms a monotonic bias from −70 V to −58 V across five dies while keeping the local substrate voltage constant. To survive an open circuit, DTI isolation separates three independent voltage domains (pixel/power, bias generation, and inter-stage detection), so that a stage can be shorted locally through a redundant path before it trips on over-voltage, keeping the chain current stable. Finally, spread-spectrum suppression lowers the EMI peaks introduced by switching. For data transport across the floating ground, an AC-coupled LVDS link provides a ground-fault-tolerant serializer channel, and transmission is gated off during power-rail switching, occupying less than 1% of the transmission time to secure signal stability.
Future work integrates the hybrid buck with inter-stage coordination to raise transfer efficiency, adds the ultra-low-dropout LDO and open-circuit monitoring, evaluates noise levels and sources, and considers radiation effects and radiation hardening.

Speaker: Dr Yue Zao (Nankai University)

11:36 A 20.48-Gbps PAM4 transmitter with 2-tap FFE in 55 nm for high-energy physics experiments

High-energy physics experiments require increasingly high-speed data transmission in front-end readout systems. Based on our prior designs and measurements, the 10-Gbps NRZ transmission is approaching the bandwidth limit of the 55-nm CMOS process. Consequently, PAM4 transmission technology, which doubles the data rate within the same analog bandwidth, presents an attractive alternative.
The proposed PAM4 transmitter comprises a phase-locked-loop (PLL), two 16:1 CMOS-logic serializers (MSB and LSB), current mode logic (CML) buffers, voltage-controlled delay cells (VCDLs), a PAM4 combiner, digital-to-analog converters (DACs) and a serial peripheral interface (SPI). The PLL and serializer circuits have been silicon-verified. To reduce area in the initial prototype, a much smaller PRBS7 pattern generator is used instead of the serializer, and the PLL is replaced by an external-clock receiver (equalizer).
The PAM4 combiner merges the MSB and LSB channels into a single data stream, providing an output current of 3 mA at a single eye height and a programmable biasing current for the vertical-cavity surface-emitting laser (VCSEL) ranging from 0.4 to 9.8 mA. A variant incorporating a peaking inductor is also implemented. The MSB channel consists of two identical LSB channels, each featuring a two-tap CML structure (referred to as the main tap and the post tap). The feed-forward equalizer (FFE) operates as a transversal filter based on a tapped delay line and the combiner. In the LSB channel, the main tap, driven by the original signals, serves as the driving stage with a tail current (M5) of about 6 mA. The post tap functions as the equalizing stage and is driven by the delayed signals. The FFE weight coefficient can be adjusted via a 4-bit tail current source (M6-M9) from 0 to 1.5 mA in 0.1-mA step. The tap delay is configured by a 10-bit DAC, providing a tuning range from 27 ps to 97 ps. By adjusting the weight coefficient and tap delay, an optimal eye opening can be achieved for a certain range of the channel loss.
Preliminary electrical test results indicate that the PAM4 transmitter operates correctly up to 20 Gbps. The three measured eye heights are 177, 193, and 193 mV after FEE (level-7), respectively. The overall power consumption is about 68.4 mW, including 15 mW (simulated) for the PRBS generator, 24 mW for the combiner alone, and the remaining power for the adjustable delay line operating with a 0.6-V control voltage.

Speakers: Mr Guorui Zhang (IHEP), Xiaoting Li (高能所)

11:54 Design of a Large-Area MRPC Readout Electronics System with High Granularity and High Timing Precision

Speaker: Weihao Wu (Shanghai Jiao Tong University)

12:12 The Peripheral Electronics Board - a Component of the HGTD In-detector Electronics for the ATLAS Phase-II Upgrade (remote)

Speaker: Jie ZHANG (Institute of High Energy Physics)

11:00 → 12:30 Flavor Physics: 1

Zoom Link, ID:99229612134, Code: 887914

11:00 LHCb flavour highlights and prospects

Speaker: Zehua Xu (CERN)

11:30 BESIII flavour highlights and prospects

Speaker: Prof. Liang Sun (Wuhan University)

12:00 Lepton-Flavour-Violating Axion-Like Particles at Future Colliders

Axion-like particles (ALPs) with lepton-flavour-violating couplings provide a distinctive opportunity to search for new physics at future high-energy and flavour facilities. I will discuss the phenomenology of ALPs above the muon threshold, where the decay a→eμ becomes kinematically accessible and can lead to striking signatures with very small Standard Model backgrounds. I will focus on ALP production in charged-meson, W, Z, quarkonium and τ decays, and discuss the prospects for probing these interactions at future e+e− colliders and flavour factories, complemented by fixed-target and beam-dump experiments. Particular emphasis will be given to the sensitivity of future facilities and to the interplay between different production channels and existing low-energy constraints.

Speaker: Marco Fedele

11:00 → 12:30 Future Experiment Proposals: 1

Zoom Link, ID: 91011235165, Code: 983836

11:00 The AGORA detector

Speaker: Yiming 一鸣 Li 李 (IHEP)

11:30 The IDEA detector

Speaker: Franco Bedeschi (INFN-Pisa)

12:00 The CLD detector

Speaker: James Brau (University of Oregon)

12:30 → 14:00 Lunch break

14:00 → 15:40 Flavor Physics: 2

Zoom Link, ID:99229612134, Code: 887914

14:00 The Impact of RICH Detector on Flavor Physics at CEPC

Particle identification (PID) is important for the flavor physics analysis at future $e^+e^-$ colliders. Efficient $K/\pi$ separation can improve the reconstruction of exclusive heavy-flavor decays and suppress backgrounds from particle misidentification. A Ring Imaging Cherenkov (RICH) detector is therefore being studied to provide additional PID capability in the forward and backward regions of the CEPC detector.

The forward and backward RICH geometries and their track acceptance are implemented in the CEPC detector simulation. Momentum- and angular-dependent PID response matrices are applied to charged tracks to model kaon and pion identification efficiencies and misidentification probabilities. Using CEPCSW-based simulated heavy-flavor samples at the $Z$ pole, the RICH kinematic coverage, geometrical acceptance, and PID performance are evaluated, together with their impact on signal efficiency and $K/\pi$ misidentification backgrounds.

These studies provide input for optimizing the RICH design and assessing its impact on CEPC flavor-physics measurements.

Speaker: 梓秋 杨 (Jilin University)

14:25 Lattice QCD calculation of $\Xi^{-}\rightarrow\Lambda\ell^{-}\bar{\nu}_{\ell}$ semileptonic decay

We present the first principle calculation of $\Xi \rightarrow \Lambda$ form factors employing 2 + 1 flavor gauge ensembles with lattice spacings ranging from 0.06 to 0.1 fm and pion masses between 230 and 340 MeV.

Speaker: 磊毅 李 (海南师范大学)

14:50 Automating SU(3) Flavor-Amplitude Analysis with an AI Agent

We present an AI agent designed to automate SU(3) flavor-amplitude analyses of hadronic weak decays. Starting from a specified decay process, the agent identifies the relevant SU(3) multiplets and effective weak Hamiltonian, constructs independent invariant contractions, and converts them into amplitudes for physical decay channels. It also performs consistency checks, searches for amplitude relations, and identifies experimentally unexplored SU(3)-related processes. As an illustrative application, we discuss three-body nonleptonic decays of bottom baryons. This framework aims to make extensive SU(3) calculations more efficient, reproducible, and less susceptible to algebraic errors.

Speaker: 吉 徐 (兰州大学)

15:15 Minimal Flavor Protection

MFP is a new flavor-symmetry spurion framework that provides minimal protection for generic new physics at the TeV scale to satisfy stringent FCNC bounds. It lies at the opposite end of the spectrum from the well-established MFV, opening up a broader landscape of flavor-safe TeV-scale models. Its defining features—maximal universality violation and flavor-charged currents—can both be effectively probed at a future e+e- collider. The talk is based on 2512.04159 and related work.

Speaker: Admir Greljo

14:00 → 15:30 Future Experiment Proposals: 2

Zoom Link, ID: 91011235165, Code: 983836

14:00 The ILD detector

Speaker: Mary-Cruz Fouz Iglesias (CIEMAT)

14:30 The ALFA detector

Speaker: Duccio Abbaneo

15:00 The ALLEGRO detector

Speaker: Emmanuel Monnier (CPPM)

14:00 → 15:30 MDI, Mechanics & Integration: 2

Saturday Morning: Junior Ballroom III
Zoom Link, ID: 91011235165, Code: 983836

Saturday Afternoon: Function Room 10
Zoom Link, ID: 94805716496, Code: 217749

14:00 Manufacturing and Experiment of Ultra-Light Carbon Fiber Composite Unidirectional Heat Conductive Cold Plate

This work focuses on the development of cold plate components for the CEPC detector. An ultra-light carbon fiber composite unidirectional heat conductive cold plate was manufactured by hot-pressing carbon fiber and graphene, and its thermal conductivity was optimized. The resulting cold plate exhibits a density lower than that of aluminum and a thermal conductivity higher than that of aluminum, making it suitable for low-material-budget detector applications. In addition, a thermal conductivity measurement method was investigated, and an experimental setup was established to measure the thermal conductivity of ultra-thin plates with a thickness of approximately 0.3 mm. This work provides reliable equipment support for further optimizing the thermal conductivity of the cold plate and experimentally verifies the feasibility of the proposed ultra-light cold plate for CEPC detector thermal management.

Speaker: xiaohui qian (高能所)

14:18 Status of Calorimeter mechanical design

An harmonious calorimeter idea has been proposed. We designed a new structure of ECAL and HCAL. More detailed structure information will be introduced in this report. A new cooling scheme has been proposed and test also has been carried out.

Speaker: 亚田 裴 (高能所)

14:36 Study on Heat Dissipation Performance of the Central Beam Pipe of CEPC

The contents include:
1.Current research status of beam pipes at home and abroad.
2.Background introduction of the CEPC central beam pipe.
3.Structural design of the central beam pipe.
4.Simulation of heat dissipation for the central beam pipe.
5.Progress in fabrication of experimental specimens for the central beam pipe.
6.Implementation of subsequent heat dissipation experiments on the central beam pipe.

Speaker: 健 王 (中国科学院高能物理研究所)

14:54 Preliminary air cooling test of the VTX thermal mockups

preliminary air cooling test results of the VTX thermal mockups .

Speaker: Mr Jinyu Fu (高能所)

15:12 Experimental studies for an air cooling system for the FCC-ee inner vertex

The inner vertex detector of the IDEA detector concept is based on MAPS technology, and is expected to dissipate less than about 50 mW/cm2. With such low power density air-cooling solutions can be developed. Two main mechanical arrangements for the silicon sensors are envisaged at the moment:a ‘traditional’ flat version, in which MAPS are put on top of a carbon fibre stave, and a curved sensor version, inspired to the ALICE ITS3 vertex detector. Preliminary simulations of the former geometry show that air-cooling can be successfully employed to maintain temperature control along the full length of the stave, which in the case of the longest structures are of the order of 50 cm dimensions,
although with a considerable air-flow, that in turn induces vibrations smaller than the single hit resolution of the MAPS (~3 μm). The mechanical layout of such a solution should guarantee sufficient air-cooling capabilities and keep the mechanical structure vibrations at the minimum.
To validate the effectiveness of this approach, a dedicated experimental setup has been implemented,enabling precise measurements of pressure, temperature, and flow rate within the test section for both single-layer and multi-layer configurations. The experimental system provides essential feed-back to the parallel computational fluid dynamics (CFD) studies, ensuring accurate data interpretation and reliable modelling of the airflow behaviour around the vertex detector staves. The presentation will provide a description of the mechanical and thermal solutions adopted to establish a hermetically sealed volume within the test section, in which cable routing constraints, together with the requirement to ensure efficient assembly and disassembly procedures, have represented significant technical challenges.
Presentation of the results on air-cooling performance as a function of the air-flow obtained by experimental measurement will be presented, and critically discussed.

Speaker: Gherardo Ammirabile (Universita & INFN Pisa (IT))

14:00 → 15:35 Offline Computing & Software: 2

Zoom Link, ID: 934 7906 6977, Code: 522727

14:00 JINR Distributed Computing for High-Energy Physics Experiments

In this talk, we present our experience in organizing high-energy physics
computing at JINR for data processing and analysis, drawing on examples from
the LHC, NICA, JUNO, and other experiments.

Speaker: Sergei Shmatov (JINR)

14:20 Status and Future of DIRAC and DiracX for CEPC

DIRAC has long served as a key middleware solution for distributed computing in high‑energy physics. Since 2012, IHEP has operated a DIRAC‑based system for BESIII, and has since extended it to support CEPC Monte Carlo production and JUNO data processing, maintaining a stable job success rate of over 95%. The platform offers integrated workload and data management, supporting heterogeneous resources—including HTC, HPC, and cloud infrastructure—across multiple international sites.

After 15 years of evolution, the DIRAC Consortium has undertaken DiracX, a cloud‑native, RESTful reimplementation built on Kubernetes, OpenSearch, and S3 storage. DiracX adopts OAuth2/OpenID Connect for token‑based authentication, replacing the legacy X509/VOMS model. As of 2026, DiracX has reached production readiness, with key use cases validated by LHCb, and integrates the Common Workflow Language (CWL) to enable portable and reproducible workflows—of particular relevance to CEPC’s future computing needs.

This presentation will provide an overview of the current status of the DIRAC project and the recent progress of DiracX.

Speaker: 晓梅 张 (高能所)

14:40 Grid Data Transfer Infrastructure for CEPC

Grid Data Transfer Infrastructure for CEPC

Speaker: Xuantong ZHANG (IHEP)

15:00 Monitoring for the Distributed Computing Infrastructure

We are developing a unified monitoring framework for Distributed Computing Infrastructure (DCI), covering computing resources, storage, data transfer, and key services. Recent work focuses on automating Grafana dashboard generation and maintenance, reducing manual configuration and improving consistency across sites.

The SAM Test framework has also been refactored into a more modular service validation system for computing, storage access, authentication, and data transfer. This presentation will introduce the monitoring architecture, Grafana automation, SAM Test redesign, and operational experience from production environments.

Speaker: Dr Xiao Han (Institute of High Energy Physics, CAS)

15:20 Integration of AI Large Language Models in High Energy Physics Research Workflows

Recent developments in artificial intelligence, particularly large language models (LLMs), have shown promise for improving productivity in high-energy physics. While there has been published work on the use of LLMs for data processing, very little has been published on their application to high-energy physics (HEP) research workflows.

In this paper, we describe our efforts to apply LLMs and AI agents to improve physics research workflows, with particular emphasis on how HEP research workflows differ from those of other fields, such as enterprise computing. Specifically, we describe our efforts to integrate LLMs into open-source computation engines such as Jupyter, and we describe how we have integrated tools such as OpenWebUI, LiteLLM, and Traefik into an integrated AI platform suitable for small research groups.

We then present our experiences with AI in research discovery, pedagogy, and data processing. Our key finding is that the specific model used is not important and that freely available models are more than sufficient for daily research work; the key challenges lie in integrating these tools into harnesses and other research infrastructure. We believe that improvements in research productivity do not require advances in the LLMs themselves, but rather improvements in coordinating harnesses and agents and integrating them into computational platforms. We conclude by discussing areas where we believe further research effort should be directed.

Speaker: Joseph Wang (Bitquant Research Laboratories)

15:30 → 16:00 Coffee break

16:00 → 18:00 EW and top Physics: 1

Zoom Link, ID:99229612134, Code: 887914

16:00 SMEFT fits

Speaker: Victor Miralles

16:20 Challenges and priorities for EW precision physics at FCC-ee

Speaker: Matteo Defranchis

16:40 FCC-ee top physics program overview

The Future Circular Collider (FCC) programme provides unique opportunities for comprehensive and precise studies of top quark physics. At the FCC-ee, operating at and slightly above the top pair threshold, a precise measurement of the top quark mass with a statistical and systematic accuracy down to the MeV level can be achieved through a threshold scan. Furthermore, the FCC-ee run at 365 GeV allows precise determinations of top quark electroweak couplings and top-related CKM matrix elements. Top pair production at threshold also presents the opportunity to probe quantum entanglement that is complementary to the measurements at the LHC. The interplay between observables at 365 GeV run and those at other energy points is also important for the complete FCC-ee program.

Speaker: Xunwu Zuo (EPFL)

17:00 ATLAS

Speaker: Dr 瑞(Rui) 张(Zhang)

17:20 Overview of electroweak experimental results at CMS

Speaker: Jie XIAO

17:40 entanglement and decoherence with top quarks and taus

Speaker: Guillermo García-Mir

16:00 → 18:00 Electronics & Readout Systems: 2

Zoom Link, ID: 934 7906 6977, Code: 522727

16:00 Overview and Status of the AGORA Electronic System

Speaker: Jingbo Ye

16:20 Readout electronics for ALICE FoCal pixel layer

Speaker: Shoulong（守龙） Lin（吝） (China Institute of Atomic Energy)

16:40 Progress on Wireless Data & Clock Transmission at IHEP (remote)

Speaker: Jun Hu (IHEP, CAS)

17:00 Readout system of the MAPS Tracker (remote, TBD)

Speaker: Jian LIU (Shandong University)

16:00 → 18:00 Gaseous Detectors: 1

Zoom Link, ID: 91011235165, Code: 983836

16:00 → 18:00 MDI, Mechanics & Integration: 3

Saturday Morning: Junior Ballroom III
Zoom Link, ID: 91011235165, Code: 983836

Saturday Afternoon: Function Room 10
Zoom Link, ID: 94805716496, Code: 217749

16:00 FCC-ee MDI Status

Speakers: Manuela Boscolo (INFN), Manuela Boscolo (INFN Laboratori Nazionali di Frascati)

16:18 Beam loss and collimation studies at FCC-ee

Speaker: Giacomo Broggi (CERN, Sapienza Università di Roma e INFN Laboratori Nazionali di Frascati)

16:36 Status and Perspectives for FCC-ee Detector Background Studies

16:54 The Study Status of CEPC MDI at EDR Phase

The machine-detector interface (MDI) issues are one of the most complicate and challenging topics at the Circular Electron Positron Collider (CEPC). Comprehensive understandings of the MDI issues are decisive for achieving the optimal overall performance of the accelerator and detector. The machine will operate at different beam energies, therefore, a flexible interaction region design will be plausible to allow for the large beam energy range. The design has to provide high luminosity that is desirable for physics studies, but keep the radiation backgrounds tolerable to the detectors and other related sub system components. This requires careful balance of the requirements from the accelerator and detector sides.
In this work, the latest design of the CEPC MDI and the study status of the beam induced backgrounds based on CEPC Technical Design Report (TDR) of the accelerator and the reference detector will be presented, covering the design of the beam pipe and whole IR, the estimation of beam induced backgrounds, the mitigating schemes, and also our plan towards the EDR of accelerator

Speaker: Dr Haoyu SHI (IHEP)

17:12 Impact of Beam-Induced Background on Time Projection Chambers at Future e+e- Colliders

In recent years, several next‑generation large‑scale scientific facility plans based on electron‑positron colliders have been successively launched in the field of international high‑energy physics (FCCee, CEPC, ILC, etc.). In the published conceptual designs of accelerators and detectors, the Time Projection Chamber (TPC) is widely selected as the main tracking detector owing to its unique technical advantages. The potential impact of beam background on the TPC drift electric field uniformity under high‑luminosity operating conditions is an important research direction that requires careful evaluation. Detailed studies in collaboration with the MDI collaboration are necessary to fully assess this aspect for the application of TPCs in future high‑energy collider experiments.

This study systematically evaluates beam-background effects on high-granularity readout Time Projection Chamber Detection technology for future electron-positron colliders, using a Geant4-based background simulation scheme equivalent to that adopted by the FCCee collaboration. A comprehensive framework covering multiple space-charge sources is developed, together with theoretical models for space-charge density, electric-field distortion, and electron-drift deviation. Secondary low-energy photons generated by beam background are identified as the primary space-charge source, with key physical parameters quantified under both Higgs and low-luminosity Z operation modes. An integrated solution combining interaction-region design optimization and dedicated correction algorithms is proposed to address the associated momentum-resolution effects. The optimized CEPC interaction-region design constrains the space-charge density below 1.0 nC/cm², keeping electron-drift deviations within 100 μm over most of the TPC chamber, while the correction algorithm effectively restores momentum-resolution performance. These results provide important theoretical and technical support for TPC applications in future high-energy collider experiments.

Speaker: Jianbo Zheng (高能所)

17:27 Zero Degree Calorimeter for BESIII

This talk will present the latest status of Zero Degree Calorimeter at BESIII. The structure of ZDC is inspired by the CEPC LumiCal which is made of Lyso crystal and SiPM.
Its primary goal is to measure the instantaneous luminosity of BEPCII and can be extended to tag the ISR photon.

Speakers: yuhui miao, 雷(Lei) 张(Zhang) (南京大学(Nanjing University))

17:45 Developing Status of CEPC Detector Magnet

The developing progress of the CEPC detector magnet is introduced in the report, including the Box-type aluminum stablized NbTi Rutherford cable and HTS cable.

Speaker: Feipeng NING (IHEP)

18:30 → 21:00 Banquet

Sunday, 25 October

09:00 → 10:30 Accelerator: 9

Zoom Link, ID: 94805716496, Code: 217749

09:00 On the synchrotron injection of the SuperKEKB

Speaker: Iida Naoko

09:20 CEPC Linac EDR status

Speaker: Jingru Zhang / Cai Meng

09:40 CEPC polarized electron source R&D in EDR

Speaker: Xiaoping Li

10:00 CEPC polarization study EDR status

Speaker: Zhe Duan

09:00 → 10:40 EW and top Physics: 2

Zoom Link, ID:99229612134, Code: 887914

09:00 Two-Loop Electroweak Renormalization in the Standard Model and NNLO Corrections to H2bb

Next-generation high-energy colliders, including the HL-LHC, and proposed Higgs factories such as FCC-ee, ILC, and CEPC, aim to probe selected Higgs and electroweak observables at the per-mille level. Achieving the required theoretical precision demands NNLO electroweak predictions alongside high-order QCD corrections. However, complete NNLO EW calculations in the SM remain scarce, with a key bottleneck being the absence of a complete and reusable two-loop EW renormalization framework. In the first part of this talk, I will present our progress toward constructing and validating a complete two-loop on-shell EW renormalization framework for the SM. The discussion will cover mass, field, mixing, and charge renormalization constants, together with sub-loop renormalization, electroweak input schemes, and the treatment of unstable particles. The second part will focus on the framework’s first phenomenological application: the pure NNLO EW and mixed QCD-EW corrections to the fully inclusive decay width of the Higgs decay proccess $H \to b \bar{b}$. I will discuss the numerical impact and interplay of these corrections, examine their dependence on the EW input scheme, and compare independent implementations in the Feynman–'t Hooft and Landau gauges.

Speaker: 哲 黎 (山东大学)

09:20 Mixed EW–QCD corrections to the diphoton decay of the Higgs boson

The diphoton decay of the Higgs boson is one of the original discovery channels and remains a golden channel for probing the properties of the Higgs boson. In this talk, I will present the first complete three-loop mixed electroweak–QCD corrections to this decay channel. The corresponding phenomenological predictions will also be discussed.

Speaker: Wen-Long Sang (SouthWest University)

09:40 The Quantum Magic of Standard Model Parameters

The scattering of microscopic particles generically gives rise to highly structured quantum final states. A growing body of work has begun to explore whether the quantum-information characteristics of these states are merely emergent, or whether they encode deep principles of the underlying quantum field theory. Among these characteristics is magic, or non-stabilizerness, which measures the intrinsic nonclassical computational power of a quantum state. We present evidence that a fundamental parameter of the Standard Model—the weak mixing angle—may be selected by minimizing the magic of the final states arising from simple lepton scattering processes. These observations motivate a systematic exploration of particle scattering from the perspective of quantum information theory.

Speaker: Zhewei Yin (IHEP)

10:00 Factorization scale and scheme dependence in higher-order ISR corrections

Higher-order contributions due to initial state radiation (ISR) in electron-positron annihilation processes are analyzed analytically and numerically. Effects due to variation of factorization scale and scheme choices in ISR are studied. A new procedure for exponentiation of higher-order next-to-leading photonic and pair corrections is suggested. The results are relevant for increasing the precision of theoretical description of general electron-positron annihilation processes at high energies. The talk is based on recent works: arXiv:2511.00437, 2606.11742 [hep-ph].

Speaker: Andrej Arbuzov (Joint Institute for Nuclear Research)

10:20 Implementation of higher-order QED ISR corrections in ZFITTER

Recent analytic results on higher-order QED radiative corrections are implemented into the ZFITTER computer code. Certain corrections in the previous version of the program in $O(\alpha^2)$ and $O(\alpha^3L^3)$ orders are applied. Higher order contributions in the leading and next-to-leading logarithmic approximation are added. A new exponentiation procedure is used. Numerical results are presented for the typical energies of future collider projects.

Speaker: Uliana Voznaya (JINR)

09:00 → 10:30 Gaseous Detectors: 2

Zoom Link, ID: 91011235165, Code: 983836

09:00 → 10:30 PID & Emerging Technologies: 1

Zoom Link, ID: 934 7906 6977, Code: 522727

10:30 → 11:00 Coffee break

11:00 → 12:30 Posters: 1

12:30 → 14:00 Lunch break

14:00 → 19:00 Free time

Monday, 26 October

09:00 → 10:40 Accelerator: 10

Zoom Link, ID: 94805716496, Code: 217749

09:00 On accelerator activities in Tsinghua University

Speaker: Lianmin Zheng

09:20 BEPCII UP status

Speaker: Dou WANG (IHEP)

09:40 BEPCII UP beam-beam effects

Speaker: Chuntao Lin

10:00 CCEPC impedance budget update in EDR (including collimators) and limitation to luminosities

Speaker: Na Wang

10:20 CEPC electron cloud effects in EDR

Speaker: Yudong Liu / Siyuan Feng

09:00 → 10:40 EW and top Physics: 3

Zoom Link, ID:99229612134, Code: 887914

09:00 New developments in ReneSANCe

We present recent updates to the ReneSANCe Monte Carlo event generator.
ReneSANCe provides one-loop EW and higher order corrections for the processes
$e^+e^- \to HZ$, $e^+e^- \to ZZ$, $e^+e^- \to \gamma Z$ and processes used for luminosity monitoring.
We have taken the first steps to enable decays of final state unstable particles and radiative corrections in decays. All spin correlations are strictly preserved.

Speaker: Dr Vitaly Yermolchyk (Joint Institute for Nuclear Research)

09:20 Polarized gamma-gamma collisions in the ReneSANCe event generator

We give a report on new developments in the gamma-gamma collision mode of the ReneSANCe Monte Carlo event generator. Results for a number of polarized Standard Model processes will be presented for future gamma-gamma colliders based on ee-colliders where high energy photons are produced via Compton backscattering of laser beams.

Speaker: Renat Sadykov (Joint Institute for Nuclear Research)

09:40 Longitudinal Λ Polarization in Tagged Z → ss̄ Events with the CEPC AGORA Detector

We present a full-simulation study of longitudinal Λ polarization in strange-tagged Z → ss̄ events with the AGORA detector at CEPC. A source-dependent polarization model, based on the OPAL benchmark, is implemented directly in event generation and propagated through the CEPC AGORA detector full simulation and reconstruction. Strange-jet tagging and Λ → pπ reconstruction define an inclusive sample and two disjoint categories with distinct Λ source compositions. Polarization is extracted from the reconstructed decay-angle distributions, with an independent unpolarized simulation used to model the detector response. The analysis recovers the injected inclusive polarization and enables a source-resolved extraction of the direct-primary-s Λ polarization together with a common polarization for Λ from Σ, Ξ, and Ξ sources. We demonstrate closure with the current simulated samples and project the sensitivity to a Tera-Z dataset, providing a framework for precision studies of strange-quark polarization transfer in Z decays.

Speaker: 民洽 李 (中国科学院高能物理研究所)

10:00 Measurements of Forward-Backward Asymmetries and the Weak Mixing Angle at the CEPC Z-pole with Particle Transformer

The Z-pole operation of CEPC will provide a large data sample for precision electroweak measurements. We present measurements of the forward-backward asymmetries $A_{FB}$ in Z decays using the CEPC reference detector simulation, and further derive the effective weak mixing angle $\sin^2\theta_W^{\mathrm{eff}}$ from these observables. The Particle Transformer deep learning architecture is employed to improve the efficiency and purity for bottom, charm, and strange quarks. Based on the resulting tagging performance, we extract the asymmetry observables and evaluate their statistical uncertainties, along with the corresponding precision of $\sin^2\theta_W^{\mathrm{eff}}$ under unpolarized beam conditions.

Incorporating beam polarization inspired by SLD, we simulate longitudinally polarized cross-sections to assess its enhancement on the weak mixing angle measurement. Beyond statistical precision, we provide both qualitative and quantitative evaluations of major systematic uncertainties with detailed assessments of their impacts on our results. Our study demonstrates that the combination of polarization and advanced AI could push the precision of these electroweak observables at CEPC to a globally leading level.

Speaker: Libo Liao (SYSU)

10:20 Two-loop mixed QCD-EW corrections to bottom pair production\\ in electron-positron collisions

We present the two-loop mixed strong-electroweak virtual corrections to the production of a massive bottom-antibottom quark pair in electron-positron collisions. The evaluation of all the relevant Feynman integrals, including those with up to five internal massive lines with three different mass values, has been worked out relying on semi-analytical techniques, using complex-valued masses for the electroweak gauge bosons. The ultraviolet-renormalized and infrared-subtracted finite correction contributes to the NNLO QCD-EW cross section of the inclusive production of a bottom-quark pair. The methodology adopted in this calculation can be extended to the study of fully electroweak second-order corrections to benchmark precision scattering processes.

Speaker: Dr Jiang Zhu (Tsung-Dao Lee Institute, Shanghai jiao tong Univercity)

09:00 → 10:30 PID & Emerging Technologies: 2

Zoom Link, ID: 934 7906 6977, Code: 522727

09:00 → 10:30 TDAQ & Online Computing: 1

Zoom Link, ID: 91011235165, Code: 983836

Conveners: Dr Fei Li (EPC, IHEP), Miroslav Saur (Lanzhou University)

09:00 Enhancement of the Belle II High Level Trigger Using GPUs

With the increasing luminosity of SuperKEKB, the background rate in
the Belle II detector is expected to increase, potentially exceeding
the processing capacity of the current High Level Trigger (HLT)
system. To mitigate the HLT processing load, we are developing a
GPU-based pre-filtering system that performs part of the event
reconstruction on GPUs before the conventional HLT processing. We have
integrated CUDA into the Belle II software framework to establish a
seamless execution environment across GPUs and CPUs. In this
presentation, we will report on the current status and progress of the
development.

Speaker: Prof. Ryosuke Itoh (KEK)

09:25 The incoherent pair production simulation study

Incoherent electron–positron pair production, commonly referred to as beamstrahlung, constitutes the dominant beam-induced background for the CPEC, accounting for more than 95% of the total background events. Reliable modeling of this process is therefore essential for both detector response estimation and trigger system design. At present, the Guinea-Pig simulation package is employed to generate this incoherent pair-production background. To validate the Guinea-Pig predictions, we analyze open data from the DELPHI experiment at LEP1 and LEP2 to measure the production cross section and momentum distribution of the produced pairs, and we compare these measurements with the corresponding simulation results.

Speaker: Boping Chen

09:50 L1 trigger hardware design progress on CEPC ref-Detector

The Circular Electron–Positron Collider (CEPC) will pursue a broad physics program by operating at several center-of-mass energies and luminosity levels, including Higgs, Z, and W-pair modes. This range of operating points places diverse requirements on the detector and its trigger and data acquisition (TDAQ) system. The trigger system is organized into two levels: a Level-1 (L1) trigger for real-time hardware-based event selection and a High-Level Trigger (HLT) for subsequent event processing. At the heart of the L1 system is the trigger data-processing module, which must handle data from multiple sub-trigger systems while meeting stringent requirements on throughput, latency, and flexibility. I. These requirements motivate the development of a shared and adaptable processing platform.To address this need, we have developed a common trigger data-processing module intended for use across the CEPC sub-trigger systems. By sharing a common hardware platform, the design aims to streamline development, integration, operation, and maintenance while allowing the same module to be adapted to different trigger applications. The module is implemented in the Advanced Telecommunications Computing Architecture (ATCA) form factor and is centered on an AMD Virtex UltraScale+ field-programmable gate array (FPGA). Eleven Quad Small Form-factor Pluggable (QSFP) modules provide 44 high-speed lanes, each supporting data rates of up to 25 Gb/s. The module also incorporates 16 GB of Double Data Rate (DDR) memory to support temporary event buffering for hundreds of milliseconds, together with an Intelligent Platform Management Controller (IPMC) and a K26 system-on-module (SOM) for board-level management and control. To date, a series of board-level functional tests has been carried out on the prototype module, covering the on-board power supply and distribution subsystem, clock distribution, FPGA configuration ,gigabits transceiver(GT) links, and DDR. The results obtained from these tests are consistent with the expected behavior of the corresponding subsystems. Testing of the K26 SOM-related functionality remains ongoing . Together, the module design and the completed tests provide a common hardware foundation for future L1 trigger-firmware integration, system-level verification, and adaptation to the requirements of different CEPC sub-trigger systems and operating modes.

Speaker: dong Liu (中国科学院高能物理研究所)

10:10 Development and Evaluation of an FPGA-Based RoCEv2 Protocol Stack for High-Throughput Data Transfer in Detector Readout Systems

Modern particle physics detectors contain many readout channels that continuously produce large amounts of data. These data must be transferred from back-end electronics to readout servers with high bandwidth and low latency while keeping CPU processing and memory-copy overhead low. This work presents an FPGA-based RoCEv2 protocol stack designed for detector data readout. The protocol stack uses RDMA to write detector data directly into registered server memory. Versions for 10, 40, and 100 GbE have been developed. The main functions include RoCEv2 packet generation, RDMA Send and Write operations, packet sequence management, iCRC calculation, and data integrity checking. The 10/40 GbE version also supports multiple queue pairs, fault isolation, retransmission, and error recovery. These functions are being added to the 100 GbE version.
The protocol stack was tested on several FPGA platforms with commercial RNICs. The 100 GbE implementation on a Xilinx VCU118 achieved approximately 93.5 Gbit/s in single-QP RDMA Write tests. Preliminary tests also measured a point-to-point latency below 3 μs. The 40 GbE implementation reached 37.4 Gbit/s, corresponding to 93.5% link utilization, and was ported to the ZCU102 platform with similar performance. Its use in a detector readout system was tested during BESIII Main Drift Chamber beam and cosmic-ray runs, where a single readout node sustained a data rate of 13.4 Gbit/s while transmitting full detector data without zero suppression.
The results show that the FPGA-based RoCEv2 protocol stack can work with commercial RNICs and provide near-line-rate transmission for particle physics detector readout. Possible future applications include the CEPC data acquisition system and other high-rate detector systems. Future work will add multi-QP and reliability support to the 100 GbE version, test multiple readout nodes, and develop a remote circular buffer for continuous and reliable data transfer.

Speakers: Sheng Dong (IHEP), 畅 徐 (高能所)

10:30 → 11:00 Coffee break

11:00 → 12:40 Accelerator: 11

Zoom Link, ID: 94805716496, Code: 217749

11:00 Radiation in the tunnel and protection for CEPC EDR

Speaker: Guangyi Tang

11:20 CEPC dumps and the dump experimental hall EDR status

Speaker: Zhongjian Ma

11:40 CEPC/SppC compatibility

Speaker: Yiwei Wang

12:00 SppC high field magnet

Speaker: Qingjin Xu

11:00 → 12:30 PID & Emerging Technologies: 3

Zoom Link, ID: 934 7906 6977, Code: 522727

11:00 → 12:30 Sustainability in HEP: 2

Friday Afternoon: Function Room 11
Zoom Link, ID: 934 7906 6977, Code: 522727

Monday Morning: Junior Ballroom I
Zoom Link, ID:99229612134, Code: 887914

11:00 → 12:30 TDAQ & Online Computing: 2

Zoom Link, ID: 91011235165, Code: 983836

Conveners: Da Yu Tou (Tsinghua University), Dr Fei Li (EPC, IHEP)

11:00 Research on GPU Algorithms and Online Computing

The Circular Electron Positron Collider (CEPC) is a next-generation high-energy electron–positron collider. Its Reference Detector will generate large volumes of data, placing demanding requirements on the trigger and data acquisition system. A fully software-based trigger offers flexible deployment, straightforward upgrades, and extensible algorithm support, while introducing substantial computational demands.

This dissertation focuses on online data processing for the CEPC and investigates two key aspects. First, GPU-oriented track-based filtering algorithms are studied and evaluated in terms of physics performance, processing latency, and throughput. Second, a heterogeneous CPU–GPU online computing framework is developed to support time-slice data organization, heterogeneous memory management, and task scheduling, providing a unified and extensible execution environment for online algorithms.

This work provides an algorithmic and software foundation for building a flexible, high-throughput, and sustainable online data processing system for the CEPC.

Speaker: 叙 张 (高能所)

11:20 Nonlinear Track Reconstruction Studies towards UKF-Based Tracking for CEPC

The development of robust, precise and computationally efficient track reconstruction is important for CEPC offline reconstruction and its future high-level trigger (HLT) development, where tracking algorithms must balance reconstruction performance with the computational demands of large-scale event processing. In particular, charged-particle motion in magnetic fields and interactions with detector material introduce nonlinearities that can affect the estimation of track states and their uncertainties. Motivated by these considerations, this work investigates nonlinear effects within the ACTS-based tracking framework as a step towards the development and evaluation of Unscented Kalman Filter (UKF)-based tracking for CEPC.

As an initial study, we investigate the ACTS FreeToBoundCorrection (FTBC), which supplements the conventional linearised free-to-bound covariance transformation with a correction for nonlinear effects. We found that FTBC was not being applied in the Combinatorial Kalman Filter (CKF) propagation path used in our study and have enabled and systematically evaluated its use. While FTBC provides an additional correction for nonlinear effects not fully captured by the linearised transformation, the underlying filtering approach still relies on conventional linearisation. The UKF, in contrast, propagates sigma points through nonlinear transformations and reconstructs the state and covariance from their transformed distribution, allowing nonlinear effects to be incorporated directly into the estimation process. The FTBC study therefore establishes a baseline for determining whether UKF-based estimation can provide additional advantages.

Controlled simulation studies are used to examine the influence of FTBC on predicted and filtered track states, covariance transport and measurement association. The results show that small FTBC-induced changes in the propagated state and covariance can, under particular trajectory and incidence conditions, alter the source-link selected during combinatorial reconstruction. Selective suppression studies further demonstrate that a correction introduced at an upstream detector surface can influence a measurement-association decision several surfaces later. In a representative trajectory, suppressing the upstream correction removes the later association switch, whereas suppressing corrections at intermediate and switching surfaces does not. These observations demonstrate how small continuous changes in state and uncertainty propagation can interact with discrete decisions in the reconstruction chain.

The dependence of these effects on track momentum and incidence conditions is being investigated, providing a controlled baseline for studies in realistic CEPC detector configurations. Ongoing work will extend the framework towards UKF-based track fitting and reconstruction and compare it with conventional Kalman-filter-based estimation in terms of state accuracy, uncertainty propagation, robustness under nonlinear conditions, measurement association and computational requirements. Such studies will help assess the potential of nonlinear filtering methodologies for future CEPC offline reconstruction and HLT applications.

Speaker: Dr Jahanzeb Akhtar (Glasgow Caledonian University)

11:40 The LHCb Heterogeneous Framework in Run 3 and Its Evolution Towards Run 4

LHCb's Run 3 trigger is a fully software-based, two-stage system operating at the full 30 MHz bunch-crossing rate, a first for a collider experiment. HLT1, built on the GPU-accelerated Allen framework, performs the real-time reconstruction and selection that reduces the input rate to a manageable level, while HLT2, built on Gaudi, performs the full offline-quality reconstruction on the surviving events. This heterogeneous CPU/GPU model has been a remarkable success: it delivers the physics performance LHCb needs and has proven the viability of GPU-accelerated real-time analysis in a running experiment.

As we look towards Run 4 and Run 5, the computing challenge grows substantially. The most promising path forward is to port more, and eventually most, of the HLT2 reconstruction to GPU, so that the full trigger chain can benefit from the same acceleration that made HLT1 possible. Realising this ambition requires more than porting individual algorithms: it requires a single, coherent framework in which GPU and CPU algorithms can be developed, composed, tested, and run together, rather than the several disconnected execution paths that exist today.

This talk will present LHCb's experience with the Run 3 heterogeneous trigger, the lessons learned from operating two separate frameworks, and the ongoing consolidation effort that unifies them into a single scheduler supporting mixed GPU/CPU sequences. We will discuss the design of this unified framework, the new mechanisms that allow GPU and CPU data to flow between algorithms, and how this positions LHCb to progressively move HLT2 reconstruction onto GPU for Run 4.

Speaker: Arthur Hennequin (CERN)

12:05 Experience with online processing of the ALICE TPC in LHC Run 3

ALICE is the dedicated heavy-ion experiment at the LHC at CERN.
For LHC Run 3, ALICE upgraded the TPC with a GEM readout to support continuous operation and the recording of all Pb-Pb collisions.
The peak Pb-Pb recording rate increased from around 1 kHz to 50 kHz.
In order to keep up with the increased data rate, ALICE upgraded its whole online computing scheme, and performs full online processing of all recorded data for calibration and for data compression.
ALICE was the first LHC experiment to leverage GPUs for online data processing during LHC Runs 1 and 2.
In Run 3, TPC processing accounts for more than 90% of the total online workload and runs entirely on GPUs.
This includes clusterization, tracking, and compression.
To efficiently use its online processing farm for offline reconstruction when the LHC is not operating, ALICE has been running offline TPC tracking on GPUs since 2023.
Meanwhile, ALICE has offloaded additional reconstruction steps to GPUs to improve the utilization of GPUs during offline reconstruction.
Online track reconstruction of a TPC with continuous readout posed several new challenges, in particular the absense of a priori knowledge of the z position of hits in the TPC.
The talk will give an overview of the novelties of TPC reconstruction in Run 3, and in particular of the challenges of online processing in such high-rate environments.

Speaker: David Rohr (CERN)

12:30 → 14:00 Lunch break

14:00 → 15:30 Plenary: 3

Thursday Morning: Grand Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

Monday Afternoon: Junior Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

14:00 The experiment proposals of FCC-ee

Speaker: Paolo Giacomelli (INFN-Bo)

14:30 BEPCII: Three Decades of Evolution and the Road Ahead

Speaker: Jiuqing Wang (IHEP)

15:00 Basic R&D of Superconducting Cavities for Future Circular and/or Linear Colliders

Speaker: Akira Miyazaki

15:30 → 16:00 Coffee break

16:00 → 18:00 Plenary: 4

Thursday Morning: Grand Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

Monday Afternoon: Junior Ballroom
Zoom Link, ID: 934 7906 6977, Code: 522727

16:00 Flavor physics at LHCb/Belle II/BES III and opportunity for future Z factory

Speaker: Vincenzo Maria Vagnoni (INFN/Bologna)

16:30 Quantum Sensing for (low and) high energy particle physics

An overview of ongoing developments and speculative ideas for greatly improved or novel detectors relying on quantum effects and relevant to the field of particle physics will be given. A particular focus will be placed on ideas addressing calorimetry, tracking, timing or other challenges relevant to high energy particle physics experiments, but some low energy applications linked to particle and fundamental physics will be discussed as well.

Speaker: Michael Doser

17:00 Beam induced background at e+e- collider

Speaker: Daniel Schulte (CERN)

17:30 Closing