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 (online)

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: Calorimeter

11:00 [C01] Shower Shapes and Data-Driven Simulation Studies using a Highly Granular Crystal ECAL

Longitudinal and lateral electromagnetic shower shapes for a highly granular crystal electromagnetic calorimeter were studied by fitting published shower profile models using experimental data from a 2025 testbeam experiment performed at the Proton Synchrotron (PS) at CERN, on an event-by-event basis. Values for the radiation length, critical energy, and Molière radius were extracted from the moments of the distributions of the shower shape parameters and measured to be consistent with published values for BGO. The distributions of the relative energy fluctuations within an event were found to be conditionally dependent upon the shower profile parameters and known distributions with good agreement. Generative methods were developed to simulate shower shape parameters and to simulate full showers conditioned on shower shape parameters extracted from data. The resulting simulated values were found to be close to or indistinguishable from real events.

Speaker: Jack ROLPH JACK CHRISTOPHER HUTCHIN (IHEP)

11:00 [C02] The Progress of the super long wiring of Drift Chamber

A drift chamber(DC)-based design has been chosen and done as a possible alternative to the TPC, in order to contribute its PID performance in the CEPC reference detector’s design [1].
One hand is to study and optimize the resolution of d𝑁/d𝑥 with the advanced electronics and the multilayer DC prototype .Thanks to the nice collaboration with the Italian group, after the study of the simulation and the preliminary test, two short multilayer drift chamber prototypes have been developed and tested with the cosmic ray and the beam at CERN PS, respectively [2, 3].
Another hand is to try the DC’ conceptual length wiring, since there hasn’t been any records or experiences in the known experiments with such a super long 5-5.8 meter single wire as one channel.
This work would like to focus on the latter and report the progress of DC’s super-long wiring as a poster if it could be accepted. It will concern:
1) Mechanical tooling for measuring the tensile limit has been optimized.
2) A tooling for a super-long wiring has been designed and machined.
3) The unit array wires as long as 5.3m has been wired. The creep of the wires has been calculated.
Furthermore, the key components and the construction standard during this work, as well as the wire-tension and dark currents will be reported.

References
[1] CEPC Reference Detector Technical Design Report
[2] CEPC_workshop_Procacci, Barcelona, 16Jun.2025
[3] CEPC_workshop_Dong Mingyi, Lisbon, 9Apr.2026

Acknowledgments
The author would like to thank BESIII-MDC and inner-DC group for the helpful records on the technology. This work was supported by the State Key Laboratory of Particle Detection and Electronics (SKLPDE-ZZ-202408).

Speaker: 董 静 Jing DONG (高能所)

11:00 [C03] Investigation of Time Projection Chamber Technology at Z operation for Future e+e- Colliders

Future electron-positron colliders, such as CEPC, FCC-ee, and ILC, are being proposed for precision studies of the Higgs boson, electroweak physics, and flavor physics. These ambitious physics programs require excellent particle identification (PID) over a wide momentum range. The Time Projection Chamber (TPC), with its low material budget and excellent tracking capabilities, is the baseline main tracker detector for these colliders. With high-granularity readout and cluster-counting techniques, the TPC offers significant potential for achieving the demanding PID performance.

This poster presents recent studies on the PID performance and readout pad-size optimization for the CEPC-TPC. A full simulation chain, based on Geant4 and Garfield++, has been developed to model the TPC response from primary ionization to digitized signals. Using a layered truncated-mean algorithm, we systematically evaluate the π/K separation power as a function of pad size, demonstrating that a 500×500 µm² pad size achieves >3σ separation up to 20 GeV/c, while providing a balance between performance and engineering feasibility. In addition, we address the critical challenge of beam-induced background at high-luminosity operation. Our simulations show that the space charge effect, arising from accumulating positive ions, can significantly degrade the momentum resolution at the Z-pole. We present strategies to mitigate this effect, including MDI optimization, which is shown to substantially recover the TPC's intrinsic performance.

These studies provide essential input for the TPC design in future high-energy collider experiments and inform the development of robust operational strategies.

Speaker: Jinxian Zhang

11:00 [C04] Particle Identification for a Highly Granular Calorimeter Prototype

A proposal for the CEPC ECAL is a highly granular scintillating crystal design that uses SiPMs to measure physics signals from photons. The potential to develop particle identification methods using deep and traditional machine learning is explored. A contrastive learning technique was demonstrated to enable the separation of showering and ‘punch-through’ pions without explicit labels. A supervised PID was then trained using the results, using both a graph neural network and a boosted decision tree to distinguish electron, showering hadron, and minimum-ionizing-particle-like events. The classifier achieved an area under the receiver operating characteristic curve of greater than 99% for both cases. A SHAP analysis showed the boosted decision tree classifier matched expectations for each event type.

Speaker: Jack ROLPH JACK CHRISTOPHER HUTCHIN (IHEP)

11:30 [C05] Study of cluster counting method for CEPC drift chamber

Flavor physics and jet measurements at the Circular Electron Positron Collider (CEPC) impose stringent requirements on particle identification (PID). The drift chamber is a key candidate for the tracker, and primary ionization cluster counting (dN/dx) offers superior PID by resolving individual ionization clusters. Simulations indicate that an optimized dN/dx drift chamber can achieve K/π separation exceeding 3σ for momentum up to 20 GeV/c.

To investigate this technique, a multi-channel drift chamber prototype was developed, using 20 μm gold-plated tungsten sense wires and 70 μm aluminum field wires. The wire parameters and cell dimensions maintain complete compatibility with the CEPC drift chamber design parameters. Concurrently, a 1.3 Gsps high-speed readout electronics system with high bandwidth and low noise characteristics has been developed, together with a DAQ system. The readout chain ensures faithful capture of fast ionization signals and supports multi-channel parallel acquisition.

The hardware system provides an experimental foundation for studying the primary ionization counting method. Initial commissioning and cosmic-ray tests confirmed the electronics performance and reliable operation of the prototype, while subsequent beam tests using muon, pion, and kaon beams further validated the performance of the developed hardware system. The beam test aim to evaluate the dN/dx-based PID capability and provide references for optimizing the technical design and parameters of the CEPC drift chamber. In addition, the beam test results will be used to guide further optimization of the hardware design.

Speaker: Wenyu Pan (中国科学院高能物理研究所)

11:30 [C06] Measurement of the Spatial and Angular Resolutions of a Stereo ECal Prototype with Cosmic Rays

The Stereo ECal consists of elongated scintillator strips arranged at alternating stereo angles in adjacent layers. This configuration provides three-dimensional spatial information while limiting the number of readout channels, making it a candidate design for a highly granular calorimeter at the CEPC. In this study, the spatial and angular reconstruction performance of a six-layer Stereo ECal prototype was evaluated using cosmic-ray data and an external tracking system. A parallax-free reconstruction method based on measurements perpendicular to the scintillator strips was developed for the multilayer stereo geometry, enabling the reconstruction of three-dimensional particle trajectories. Comparisons with external reference tracks yield spatial resolutions of approximately $3.50\mathrm{mm}$ and $10.86\mathrm{mm}$ in the two transverse directions at the center of the prototype, together with an azimuthal angular resolution of approximately $3.14^\circ$. These measurements include contributions from the external tracking system and residual alignment uncertainties. The results demonstrate the capability of the stereo-strip geometry to reconstruct both particle positions and directions, providing an experimental basis for further optimization and development of the Stereo ECal for the CEPC.

Speaker: 柄焜 贺 (中科院高能物理研究所)

11:30 [C07] Performance Study of BSO Crystal Bars for High-Granularity Electromagnetic Calorimeters

High-granularity electromagnetic calorimeters employing long scintillator bars have attracted increasing interest for future collider experiments. Compared with conventional BGO crystals, BSO provides a promising alternative due to its faster scintillation decay time and cost advantage, making it a potential candidate for future ECAL applications.
In this work, we present a systematic performance study of BSO crystal bars with dimensions of $2 \times 2 \times 12\ \mathrm{cm}^3$ for a high-granularity calorimeter prototype. Beam tests at the CERN PS-T9 beamline and complementary laboratory measurements with a collimated $^{137}\mathrm{Cs}$ source were performed to characterize the scintillation response and spatial uniformity of the crystals. The beam test demonstrates an average MIP response of $282\ \mathrm{p.e.}/\mathrm{MIP}$ with intra-crystal non-uniformity below $1\%$, while the observed inter-crystal response variation can be correctedthrough calibration. Laboratory measurements further investigate the intrinsic response uniformity of individual crystals. In addition, simulations at different levels, including optical, prototype-level, and detector-level simulations, were performed to evaluate the impact of crystal response variations on calorimeter performance.
The results indicate that BSO provides sufficient light output to achieve the required calorimeter performance, supporting its feasibility as a cost-effective scintillator option for future high-granularity ECAL systems.

Speaker: Yushan Liu (Institute of High Energy Physics, Chinese Academy of Sciences)

11:30 [C08] Experimental Characterization and Optical Simulation of Scintillating Glass for the AGORA Calorimeter

Scintillating glass is a promising active material for the AGORA high-granularity calorimeter concept for future electron–positron colliders, owing to its high density, potentially high light yield, relatively low cost, and feasibility for large-scale fabrication. As part of the detector R&D program, we perform systematic laboratory characterization of scintillating-glass samples using radioactive sources and cosmic-ray muons with SiPM readout. These measurements are used to evaluate the detected light yield under different experimental conditions.

To better understand the experimental observations, a dedicated Geant4 optical simulation has been developed, including scintillation-photon generation and transport, optical surface effects, and SiPM photon detection. The simulation is configured to reproduce the experimental setup and conditions as closely as possible. A preliminary comparison between simulation and measurement shows reasonable agreement in the detected light yield, providing a basis for further studies of the optical response of scintillating glass.

The combined experimental and simulation studies provide input for understanding the optical performance of scintillating glass and for optimizing its application in the AGORA calorimeter. These studies also contribute to assessing whether the achievable photon statistics can support the targeted energy resolution of electromagnetic and hadronic calorimetry at future collider experiments.

Speaker: Yushan Liu (Institute of High Energy Physics, Chinese Academy of Sciences)

12:00 [C09] Toward Large-Diameter BaF2:Y Scintillators with Controlled Light Response: Crack-Free Crystal Growth and Optical-Transport Diagnostics

Yttrium-doped barium fluoride (BaF2:Y) is attractive for high-rate radiation detection because Y doping suppresses the slow self-trapped-exciton emission while retaining the ultrafast core-valence luminescence of BaF2. Its practical use, however, requires both scalable crystal growth and control of position-dependent light collection. We address these requirements through two complementary studies using separate large-diameter BaF2:Y ingots. In the first study, measured thermophysical properties and thermal-stress analysis were used to define allowable growth and cooling conditions for BaF2 with Y doping concentration up to 15 at.%. An axial temperature gradient of 9 °C∙cm-1 and a temperature-dependent segmented cooling schedule enabled the crack-free growth of a 4-inch-diameter, 8-cm-long crystal. The crystal maintained high visible-range transmittance over most of the measured region, although the tail-end optical quality requires further improvement. In the second study, transverse light-response uniformity was investigated using 10 × 10 × 55 mm3 bars cut from an ingot with a nominal Y concentration of 10 at.%. LA-ICP-MS showed no measurable macroscopic radial Y gradient within the selected region, yet dual-ended measurements revealed a clear position dependence in the collected response. Quotient analysis showed limited light-yield-related asymmetry and substantially larger transport-related asymmetry. Measurements under different wrapping conditions established sensitivity to the optical boundary. Under the fixed inputs used in optical-only Geant4 simulations, surface and interface losses exceeded bulk absorption. Together, these results connect thermal-field control, composition assessment and optical-boundary engineering in the development of large BaF2:Y scintillators with controlled detector response. Future work will validate the spatial and temporal response of longer crystals using controlled optical packaging and detector-representative readout conditions.

Speaker: Jing Zhang (Shanghai Institute of Ceramics)

12:00 [C10] TES spectrometer for high energy applications

Conventional semiconductor-based energy-dispersive spectrometers offer high detection efficiency but relatively limited energy resolution, whereas crystal-based wavelength-dispersive spectrometers can achieve excellent energy resolution at the cost of collection efficiency and simultaneous spectral coverage. Transition-edge sensor (TES) microcalorimeters can combine high energy resolution, high detection efficiency, and broadband spectroscopic capability.
This work describes the development of a TES-based hard X-ray spectrometer, including aluminum–manganese (AlMn) TES design, absorber optimization, electrothermal characterization, and system-level design and simulation. The spectrometer targets an energy resolving power of (E/\Delta E \sim 2000) over the 10–100 keV energy range. TES devices exploit the steep resistance–temperature dependence within the superconducting transition to resolve the small temperature rise produced by an absorbed photon. The transition temperature (T_\mathrm{c}) of AlMn films can be adjusted by annealing, which facilitates control of (T_\mathrm{c}) and its uniformity across detector arrays. A gold–bismuth bilayer absorber is used to combine the high thermal conductivity of gold with the relatively low heat capacity and high X-ray stopping power of bismuth. The absorber geometry and TES–absorber coupling are optimized for efficient thermalization while reducing position-dependent response and maintaining a balance between energy resolution and absorption efficiency. Electrothermal measurements are used to characterize device performance and guide further detector optimization and cryogenic system integration.
The development can be used for applications in hard X-ray Compton spectroscopy and X-ray emission spectroscopy at synchrotron radiation facilities. The TES detector can also be used for 511-keV positron-annihilation spectroscopy of the Galactic center.

Speaker: 浩宇 李 (中国科学院高能物理研究所)

12:00 [C11] Improved Jet Energy Reconstruction with XGBoost for the CEPC

Accurate jet energy reconstruction is essential for precision studies of hadronic Higgs, W, and Z boson decays at the Circular Electron Positron Collider (CEPC). The CEPC Reference Detector Technical Design Report reports a baseline jet energy resolution of approximately 4.5–5.0% for light-quark jets in the barrel region. Building on this benchmark, this study explores machine learning to exploit the information within individual jets and further improve jet energy reconstruction.
In this talk, we present an XGBoost-based jet energy calibration framework for simulated e^+ e^-→ZH events at a centre-of-mass energy of 240 GeV, using a comprehensive set of jet-level observables derived from particle-flow jets reconstructed with the Durham algorithm in FastJet. Preliminary results in a barrel benchmark sample show that the jet-count-weighted average of the double-sided Crystal Ball core resolutions across energy bins decreases from approximately 4.50% to 3.73%. The presentation will also assess the impact of the calibration on Higgs dijet invariant-mass reconstruction and its potential benefits for event selection and signal extraction in precision Higgs analyses.

Speaker: Yujie Xiong (Shanghai Jiao Tong University)

12:00 [C12] Surface and Bulk Defect Control of CsPbBr3 Single Crystals for Gamma-Ray Spectroscopy

All-inorganic CsPbBr3 single crystals are promising for X/γ-ray detection owing to their excellent carrier transport properties and room-temperature detection capability. However, processing-induced surface damage and bulk impurities can compromise device performance, and their effects on carrier transport and γ-ray detection remain to be systematically clarified. Herein, surface-state engineering and bulk impurity control were systematically investigated to address this challenge. A controlled stepwise polishing strategy was proposed for surface-state engineering. By this strategy, the surface roughness was decreased from approximately 20 to 2.8 nm. The surface damage layer was reduced from 3 μm to 110 nm, and the effective trap density was lowered by a factor of approximately 4.5. Consequently, the dark current of the devices fabricated on the same crystal decreased from 210 to 30.3 nA, and the energy resolution for 662 keV 137Cs γ-rays improved from 22.8% to 6.4%. Furthermore, an iterative dynamic zone-refining strategy was proposed to grow high-quality CsPbBr3 single crystals at a growth rate of 25 mm h−1, directly yielding low-impurity crystals after 40 passes. The middle region exhibited a minimum total impurity concentration of 6.1 ppm, with a hole mobility–lifetime product (μhτh) of 1.2 × 10−3 cm2 V−1. The fabricated Au/CsPbBr3/In planar detectors achieved an energy resolution of 3.4% for 662 keV 137Cs γ-rays at room temperature. Segregation-coefficient analysis and density functional theory (DFT) calculations identified Ti and Cu as key deep-level impurities limiting carrier transport. These results indicate that surface damage removal and bulk impurity control suppress surface leakage and improve carrier transport, respectively, jointly enhancing the γ-ray detection performance of CsPbBr3 single crystals. This work provides experimental evidence and design guidance for surface-state engineering and crystal growth of high-resolution X/γ-ray detector materials.

Speaker: Jie Ma (Shanghai Institute of Ceramics)

12:00 [C13] Scintillation and Radiation Damage Performance of Yttrium Doped BaF2 Crystals

Barium fluoride (BaF2) is a classic ultrafast scintillator with a sub-nanosecond fast component. Following our group's demonstration that yttrium (Y) doping effectively suppresses its intrinsic slow component, systematic investigations of the concentration-dependent scintillation performance and radiation tolerance are needed to guide its application in high-energy physics detectors. Here, BaF2 crystals with nominal Y concentrations of 0–20 at.% were systematically characterized in terms of optical transmittance, radioluminescence, light output (LO), fast-to-slow component ratio (F/S), energy resolution, and decay kinetics. Radiation damage was assessed after γ-ray irradiation at cumulative doses of 10 krad–10 Mrad. A 200-mm-long BaF2:Y crystal with a nominal Y concentration of 10 at.%, obtained via vertical Bridgman growth, was also characterized to evaluate its optical and scintillation properties and light-response uniformity.
The results reveal distinct concentration-dependent behaviors of the fast and slow components. At 20 at.% Y, the fast- and slow-component LOs decreased to 60% and 6% of those of undoped BaF2, respectively, increasing the F/S ratio from 0.13 to 1.36, while the energy resolution at 511 keV deteriorated from 12.1% to 38.7%. The two decay times of the slow component shortened from 755 to 381 ns and from 199 to 41 ns with increasing Y concentration. The 200-mm-long, 10 at.% Y-doped crystal exhibited good optical transmittance and light-response uniformity, with its slow-component intensity suppressed by approximately one order of magnitude relative to undoped BaF2. The effective Y segregation coefficient was 0.84. Regarding radiation damage, crystals containing 1–7.5 at.% Y exhibited lower emission-weighted radiation-induced absorption coefficients (EWRIACs) and relative LO losses than undoped BaF2, with the best radiation resistance at 2 at.% Y. At 10 Mrad, the EWRIACs for the fast and slow components were 4.6 and 4.0 m-1, respectively, with a relative LO loss of approximately 29%. In contrast, 10–20 at.% Y increased both radiation-induced absorption and LO loss. Phosphorescence spectra further revealed a Y-dependent redshift of broadband emission and an increasing contribution from narrowband emission. These findings provide guidance for selecting an appropriate Y doping concentration in BaF2 crystals for ultrafast radiation detection.

Speaker: Jiawei Xu (Shanghai Institute of Ceramics)

11:00 → 12:30 Posters: Silicon detector

11:00 [B01] Benchmarking APES against SAD for single beam background simulations at BEPCII‑U

This study evaluates the Accelerator Physics Emulation Studio (APES) against the Strategic Accelerator Design (SAD) code for simulating single beam background processes at BEPCII‑U, with a focus on physical modeling and computational performance. In terms of physics, APES shows good agreement with SAD in scattering generation, optical functions, beam lifetimes, and loss distributions near the interaction region; the maximum relative deviation in process specific lifetimes is approximately 1.82%, while the total lifetime deviation is below 0.3% at BEPCII‑U. In terms of computational efficiency, APES on GPU significantly outperforms its CPU version when the number of tracked particles reaches several hundred; for multi‑turn tracking of 10⁴ particles, the GPU implementation achieves a speedup of about 20 times over the CPU version and a performance improvement of about 10 times relative to SAD on CPU. These results confirm that APES can reliably model the relevant physical processes and, combined with its GPU acceleration, provides an efficient and reliable tool for single beam background studies at BEPCII‑U, with potential applicability to future circular colliders.

Speaker: 仕元 王

11:00 [B02] Radiation tolerance study of the first 55 nm HV-CMOS pixel sensor

High-voltage CMOS (HV-CMOS) pixel sensors represent a promising candidate for tracking applications in future high-energy physics experiments. Building upon the established 180 nm and 130 nm process nodes, our COFFEE2 prototype has been developed in a commercial 55 nm HV-CMOS technology to further explore the performance potential of advanced CMOS processes. The COFFEE2 chip integrates not only pixel-level circuitry for verifying basic sensor and analog front-end functionality, but also a full data-driven readout array. To evaluate its radiation tolerance, the chip was irradiated with protons at the China Spallation Neutron Source (CSNS), with a focus on key operational parameters including leakage current, signal-to-noise ratio, and overall functionality under increasing fluence. In addition, X-ray irradiation was performed to assess the device response to total ionizing dose (TID) effects. These preliminary irradiation results provide initial validation of both the COFFEE2 design and the commercial 55 nm HV-CMOS process, demonstrating its viability for future detector applications.

Speaker: 帆 胡 (中国科学院高能物理研究所)

11:00 [B03] Development Status & Plans of Serial Powering at IHEP

The increasing level of front-end integration in particle detector has placed new requirements for powering system, particularly in terms of material budget, power distribution, and system scalability. Serial powering, based on a constant current scheme with shunt-LDO regulars (SLDO), has been an attractive solution for large-scale detector systems and future collider upgrades.

This contribution presents the development status and future plans of serial powering R\&D at the Institute of High Energy Physics (IHEP), with applications to the LHCb Upstream Tracker and future Higgs-factory experiments such as CEPC.

\textbf{ATLASPix3-based SLDO tests: }The SLDO performance of ATLASPix3 chips has been systematically investigated using dedicated probe card and Single-Chip Carrier (SCC) setups. Both bare chip and chip with core cell configurations have been characterized. Four ATLASPix3 chips assembled on SCCs have been operated in series, demonstrating stable voltage regulation and functional outputs. Besides, A 1$\times$4 PCB based on a quad-flex layout has also been designed and produced for module-level serial-powering studies, with wire bonding and functional testing in progress.

\textbf{COFFEE/CHiR Chips with SLDO design: } To develop CMOS pixel sensors in a 55~nm HVCMOS processing with serial powering module, two different SLDO architectures have been implemented in the CHiR chip, including an approach following the ATLASPix3 design and another based on the RD53 architecture. Device sizes and types have been optimized for the shunt and pass devices, while an overvoltage tolerant design extends the applicable input voltage range beyond the nominal 1.2~V technology limit to approximately 2~V. Simulations have demonstrated stable regulation for both a single SLDO and a four-chip serial chain. A dedicated CHiR test PCB has been designed, with measurements planned to characterize SLDO output regulation, serial-chain operation, and load-transient response.

The ongoing development aims to demonstrate serial powering at module level and establish a practical powering solution for future low-material-budget tracking detectors, while supporting long-term collaboration with the ATLASPix community and the development of serial powering technologies.

Speaker: Tianyu Liang

CEPC2026.pdf

11:00 [B04] Fast Simulation of Incoherent Pair Backgrounds at the CEPC Using Conditional Flow Matching

Accurate simulation of beam-beam interaction backgrounds, particularly the copious production of incoherent electron-positron pairs, is essential for detector design and physics analysis at the future Circular Electron Positron Collider (CEPC). However, the high computational cost of established codes such as Guinea-Pig++ presents a bottleneck for generating the large-statistics datasets required: a single bunch crossing (BX) requires about 10 CPU-hours, while robust performance studies demand $10^4$–$10^5$ BXs.

To address this challenge, we present the first application of a deep generative model to beam-beam pair background simulation, based on conditional Optimal Transport Conditional Flow Matching (OT-CFM). The model employs a physics-informed preprocessing pipeline that decomposes particle kinematics into transverse momentum, quantile-normalized longitudinal velocity, and circular-encoded azimuthal angle, enabling accurate reproduction of the full phase space including ultra-relativistic regimes. Conditioned on the production process, a single unified network reproduces the distinct kinematics and relative fractions of all three pair production channels (Breit–Wheeler, Bethe–Heitler, and Landau–Lifshitz).

The model was trained on 5000 BXs comprising approximately 10.8 million particles generated by Guinea-Pig++ for the CEPC Higgs factory beam parameters. It achieves a Maximum Mean Discrepancy of $2.8\times10^{-5}$ and Kolmogorov–Smirnov statistics below 0.002 for the energy, transverse momentum, and angular distributions, with the longitudinal velocity reproduced at a KS level of 0.013. The surrogate provides a speedup of approximately $2.7\times10^{5}$ over single-core Guinea-Pig++ execution, reducing a 100,000-BX dataset from an estimated 114 years of single-core CPU time to under 4 hours of GPU time. These results establish conditional flow matching as a computationally efficient tool for this class of simulation problems, with direct relevance to detector optimization at CEPC and other future high-luminosity lepton colliders.

Speaker: 彦邦 唐 (IHEP)

11:20 [B05] A Unified Sensor-Front-End Optimization Framework for 55nm HV-MAPS

Monolithic Active Pixel Sensors (MAPS) in advanced CMOS nodes must balance timing, power, and noise for next-generation tracking detectors. For the CEPC Inner Tracker, the system-level requirements are a timing resolution of ~3 ns and power consumption below 150 mW/cm². Within this power budget, the analog front-end (AFE) consumes the largest fraction, making its optimization the most effective path toward meeting the overall system target. In a domestic 55nm HV-MAPS process, the sensor's deep-well configuration (VDNW/DPW) introduces significant parasitic capacitance (Cw) that dominates the front-end load, directly limiting the AFE noise and power efficiency. This work presents a design-side co-optimization framework based on an FAB-provided baseline process. A TCAD model is built and calibrated to decompose the sensor capacitance into its components (Cd vs. Cw). The front-end amplifier is then optimized using a gm/ID methodology under the extracted capacitance load. A 3×3 pixels TCAD electric-field data is imported into Allpix2 for signal collection simulation, enabling iterative feedback to the layout design. This work establishes a practical design flow for sensor-AFE co-optimization, providing a reusable foundation for the CEPC ITK pixel chip development.

Speaker: 柄辰 阎 (高能所)

11:20 [B06] Simulation and Analysis of Quantum Entanglement in Top–Antitop Pair Production Across Energy Scales

Quantum-information observables offer new tools for probing collider events beyond traditional quantities such as cross sections and invariant masses. This work investigates quantum entanglement in top–antitop pairs produced via e⁺e⁻ → tt̄, using spin density matrices generated with the recently developed Density Mode framework within MadGraph5_aMC@NLO. Events were simulated at leading order for nine center-of-mass energies between 350 GeV and 3 TeV using unpolarized beams. A custom Python pipeline was deployed to reconstruct the spin density matrices and evaluate Purity, Concurrence, Entanglement of Formation, and Negativity as functions of the top quark production angle.
The angular peak position of the entanglement observables stabilizes above ~1–1.5 TeV, settling near cos θ ≈ −0.51, in agreement with theoretical predictions once a sign-convention correction is applied to the angle definition. By contrast, the peak magnitude of these observables continues to increase up to 3 TeV, asymptotically approaching but not yet reaching the maximal mathematical bounds, consistent with residual m_t²/s corrections at the highest energy studied. Bootstrap resampling (200 iterations) confirms that this qualitative behavior is statistically robust. These results provide a systematic, unpolarized baseline for the energy evolution of quantum-information observables in the top sector, serving as a precise Standard Model reference for future high-energy e⁺e⁻ collider programs and complementing recent LHC threshold measurements.

Speaker: Ms Sima Nur Akcali (Department of Physics, NYU Shanghai)

11:20 [B07] Numerical and Experimental Investigation of Cooling-Water-Induced Excitation and Structural Response for Accelerator Magnet Applications

CEPC mechanical-stability studies specify stringent ground-motion requirements, with RMS displacement integrated over 1-100 Hz of ≤4 nm for the machine-detector interface (MDI) and ≤24 nm for the collider arc, straight and RF sections. In addition to ground-borne vibration, cooling-water systems can act as a direct source of mechanical excitation in accelerator magnet systems. Previous in situ cooling-water on/off measurements on the installed HEPS QD2 quadrupole magnet showed measurable changes in magnet vibration, motivating further investigation of the underlying fluid excitation and structural response.The present work investigates the unsteady fluid excitation generated by cooling-water flow and its relationship with structural vibration under controlled conditions. Large-eddy simulation is used to resolve transient wall-pressure fluctuations and provide distributed pressure loading for one-way fluid–structure interaction analysis. The study also incorporates controlled-flow vibration measurements on simplified piping specimens under matched flow conditions to evaluate the predicted structural response. Preliminary numerical results for the current piping model show pronounced spatial variation of pressure fluctuations, highlighting the importance of retaining the distributed nature of the pressure loading in structural-response analysis.The combined numerical and experimental study provides a basis for extending the analysis to realistic accelerator magnet cooling systems, with the ultimate goal of quantitatively predicting cooling-water-induced vibration.

Speaker: 雨琦 张

11:20 [B08] First beam test results of COFFEE3, an HV-CMOS Pixel Prototype for the CEPC Inner Tracker

COFFEE3 is a 55 nm HV-CMOS pixel detector prototype developed for the CEPC inner tracker. Following previous bench tests with charge injection, laser illumination, and a 55Fe source, two beam-test campaigns were carried out at the CERN SPS in May and July 2026. Clear responses to high-energy charged particles are observed, together with temporal correlation with scintillator reference signals. The measured single-pixel time-of-arrival (TOA) spread is studied and timewalk effect has been observed. Multi-pixel measurements demonstrated the full readout chain of the pixel array and validated the per-pixel threshold-tuning DAC (TDAC) capability. The beam tests also revealed pixel-to-pixel response non-uniformity and noise-induced hit bursts, providing important input for further optimization of COFFEE3 and the development of next-generation HV-CMOS pixel detectors

Speaker: Yuman Cai (IHEP)

11:40 [B09] Simulation and Digitization Studies of TaichuPix for the CEPC Vertex Detector

Accurate modelling of charge sharing and pixel response is essential for evaluating the performance of the Circular Electron–Positron Collider (CEPC) vertex detector, particularly for tracks at large incident angles. We present an Allpix²-based simulation and digitization workflow for TaichuPix monolithic active pixel sensors developed for CEPC, with an emphasis on the processes connecting particle energy deposition to reconstructed pixel clusters.
The workflow combines Geant4 energy deposition, electron and hole transport through imported three-dimensional electric-field maps, Shockley–Ramo signal induction, and threshold-based digitization incorporating electronic noise and threshold dispersion. Simulations of 2.5 GeV electrons at incident angles from 0° to 80° relative to the sensor normal are used to investigate charge collection, lateral charge sharing, hit efficiency, and cluster-size distributions. Comparisons with beam-test measurements provide experimental benchmarks for assessing the angular dependence of the simulated response.
Particular attention is given to the consistency between collected charge, induced signals, and the threshold decision. Controlled studies examine the effects of collection geometry, carrier termination at sensor boundaries, transport time step, and signal integration. An idealized continuously active discriminator response is also implemented to study threshold crossing during pulse development. These diagnostics identify simulation assumptions that can substantially affect the predicted cluster multiplicity and help distinguish transport effects from signal-formation and digitization effects.
We discuss the current simulation-to-data comparisons, remaining discrepancies, and priorities for further validation. This work provides a reproducible basis for refining TaichuPix digitization and supporting future studies of the CEPC vertex-detector response.

Speaker: Hancen LU (鲁函岑) (IHEP)

11:40 [B10] Heating Film Design and Temperature-Sensing Methods for VTX Thermal Mockups

A resistive heating film was developed to simulate pixel sensor and readout heat loads in the innermost layer of the vertex detector. To simplify signal routing outside the cooling chamber, two sensing configurations were designed: a flexible printed circuit (FPC) carrying 11 surface-mount PT100 sensors, and individually wired PT100 probes (manually assembled using enameled Cu wire and UV curable adhesive). The FPC option offered easier handling and was therefore selected. However, its connectors and solder pads remain mechanically fragile. Future work will expand the sensing points and improve its mechanical robustness, while silicon-based heaters are also being considered as an option.

Speaker: 子煜 刘 (Institute of High Energy Physics)

11:40 [B11] Development and Characterization of a Compact Silicon Micro-strip Tracking System

Silicon microstrip detectors provide high spatial resolution, reliable charge measurement, and a scalable detector architecture, making them well suited for charged-particle tracking, beam monitoring, and detector prototyping. In this work, we present the development and initial characterization of a compact silicon microstrip tracking system based on p-on-n strip sensors. Each detector module has 192 readout channels and an effective sensitive area of approximately 26*40 mm^2. The sensor is integrated with three 64-channel IDE1140 front-end ASICs, dedicated bias and control circuits, and a compact mechanical support structure. The system is designed to accommodate six modules arranged in three tracking stations with orthogonal strip orientations, enabling two-dimensional hit reconstruction and particle-track measurement.

The data acquisition system is built around a Xilinx ZCU102 FPGA board with dedicated firmware and control software. It supports front-end configuration, online calibration, programmable sampling delay, pedestal and noise measurements, and data acquisition using either internal or external triggers. Individual detector modules have been commissioned under a bias voltage of 50 V. The measured channel noise is typically around two ADC counts. Cosmic-ray measurements have been performed with several modules, and clear particle-induced cluster signals have been observed. A scan of the sampling delay also demonstrates its significant influence on the collected signal amplitude and detection efficiency.

The system is being integrated with a previously developed track-reconstruction framework. Together with our experience in operating an silicon beam monitor at the High Energy Photon Source, this development establishes a technical basis for compact beam telescopes and beam-diagnostic systems. Potential applications include charged-particle beam monitoring, characterization of novel detector prototypes, and tracking references for future high-energy physics experiments. The poster will present the detector design, DAQ architecture, cosmic-ray results, and the roadmap toward synchronized multi-module operation and beam tests.

Speaker: Mr Yiyang Pan (高能物理研究所)

11:40 [B12] Module Prototyping for the CEPC/AGORA Inner Tracker

Utilizing advanced 55 nm HVCMOS technology, the Inner Tracker (ITK) is a key component of the AGORA detector tracking system, originally proposed for the CEPC. The ITK features a highly modular design, with each basic module integrating up to 14 sensor chips. Pending the availability of full-size chips, prototyping efforts have commenced with dummy sensors that replicate the geometric dimensions and material composition of the final chips. Concurrently, a suite of customized assembly tools has been designed, and the assembly workflow is being established. This poster will present the latest progress in module prototyping.

Speaker: xiaomin deng (IHEP)

12:00 [B13] Development of Advanced Semiconductor Tracking Detector Systems and Key Technologies

Particle magnetic spectrometers are essential instruments in particle physics, enabling precise measurements of the momentum, charge, time of flight, and energy of charged particles. Driven by the requirements of next-generation magnetic spectrometer experiments, the project team focuses on key technologies for high-precision semiconductor tracking detectors. The project advances the development and engineering validation of high-performance silicon- and SiC-based detectors, dedicated readout electronics, high-speed data acquisition, lightweight mechanical structures, and low-temperature cooling systems. A major objective is to develop a large-area semiconductor sensor capable of simultaneously achieving a timing resolution better than 40 ps and a spatial resolution of approximately 10 μm. In parallel, a dedicated readout ASIC featuring high precision, low power consumption, and high integration density is being developed, together with a radiation-tolerant RISC-V system-on-chip (SoC) for high-energy physics applications, enabling dynamic front-end configuration, on-chip intelligent algorithms, and data processing.
The project also includes the development of high-speed data acquisition systems, low-mass, high-strength carbon-fiber support structures, and the first two-phase CO₂ cooling system for semiconductor detectors in China. These technologies will be integrated into engineering prototypes for system-level validation. Ultimately, the team aims to establish an integrated R&D framework covering the entire technology chain—from sensors and electronics to readout, mechanics, cooling, and system integration—providing a technological foundation for next-generation ground-based colliders, space-borne magnetic spectrometers, and high-precision radiation detection systems. In this talk, we will present an overview of recent detector R&D progress, system integration, and future development plans.

Speaker: Qi YAN (IHEP)

12:00 [B14] Neural-Network-Based Position Reconstruction for Strip AC-LGADs

We present a neural-network-based method for transverse position reconstruction in strip AC-LGADs for future collider applications. Laser scans of a four-strip sensor with different inter-electrode gaps and signal intensities are used to study the reconstruction performance. Neural-network approaches are compared with conventional amplitude-based methods, with particular attention to spatial resolution, generalization to untrained positions, and performance at different signal intensities. Preliminary results show that neural networks can significantly improve the position reconstruction performance, while their extrapolation capability and the information content of different waveform features are being further investigated.

Speaker: Weiyi Sun

12:00 [B15] Simulation of the Influence of JTE and p-Stop Geometry on the Breakdown Voltage of Long RSD/LGAD Sensors

Modern detector systems for particle physics, such as the outer tracker (OTK) of the future CEPC detector, aim to simultaneously improve timing and spatial resolution while reducing the amount of material in the detector and simplifying its readout electronics. One possible solution is the use of RSD-LGAD sensor strips with lengths on the order of centimeters. Such sensors can provide particle information using several neighboring readout pads.
One of the key characteristics of a semiconductor sensor is its breakdown voltage. Increasing the breakdown voltage allows the sensor's operating range to be extended and ensures stable operation at high bias voltages. At the same time, achieving a high breakdown voltage while maintaining a simple sensor structure is highly desirable. Special structural elements, such as JTE and p-stop regions, are used to control the electric-field distribution near the edges of the active area. Their geometrical parameters and relative positions affect the electric-field distribution and, consequently, the breakdown voltage of the sensor.
In this work, the influence of the geometrical parameters of JTE and p-stop regions on the electrical characteristics of strip DC-coupled RSD-LGAD sensors is investigated. Particular attention is paid to the effect of the distance between the JTE and p-stop regions on the breakdown voltage, as well as to the influence of the readout-pad geometry and the overall sensor size.
For this study, a DC-coupled RSD-LGAD sensor 2D model was developed using the Sentaurus TCAD environment, based on the structure of AC-coupled RSD-LGAD sensor described in [1]. The model consists of five main layers: p-type substrate layer, a lightly doped p-type epitaxial layer, an enriched p-type gain layer, an n-doped resistive layer, and a passivation surface layer. The structure also includes symmetrically arranged readout pads, JTE regions, n++ regions, and p-stop regions.
Using numerical simulations, the current-voltage characteristics of sensors with lengths of 400 μm and longer, were calculated for various geometrical parameters. The main parameters varied in the simulations were the distance between the JTE and p-stop regions and the distance between adjacent readout pads.
The obtained results on the influence of the geometry of edge-termination elements and the readout-pad arrangement on the sensor breakdown voltage can be used to determine an optimized RSD-LGAD sensor structure.
1. X. Zhang et al., Design of AC-coupled low gain avalanche diodes (AC-LGADs): a 2D TCAD simulation study, JINST 17 (2022) C09014.

Speakers: Violetta Maier (JINR), Mr Nikolay Atanov (JINR)

12:00 [B16] UP bare stave design and thermal study

UP bare stave design and thermal study

Speaker: 天歌 李 (Hunan University)

11:00 → 12:30 Posters: accelerator: Accelarator

11:00 [A01] Development of 1.2 Mega-Watt P-band Travelling Wave Resonant Ring

The reliable operation of high-power RF components, such as input couplers and RF windows, is critical for the Circular Electron Positron Collider (CEPC) project. Prior to installation into the accelerator system, these components require rigorous high-power conditioning to verify their RF performance and thermal stability. However, establishing megawatt-level test facilities is challenging due to the complexity and limited availability of high-power RF sources. To address this issue, the Institute of High Energy Physics (IHEP) has developed a 650 MHz traveling-wave resonant ring (TWRR) system based on a WR1500 waveguide. This system incorporates an integrated phase-shifting and impedance-matching structure using a 3 dB hybrid coupler and dual short-circuit plungers, enabling efficient RF energy accumulation within a closed-loop configuration using a relatively low-power source. During high-power continuous-wave (CW) testing, the TWRR achieved a circulating power of approximately 1.2 MW with an injected power of only 42.7 kW, corresponding to a power gain exceeding 14 dB. The system maintained stable, uninterrupted CW operation for 8 hours, with real-time temperature and infrared thermography monitoring confirming effective thermal management. These results not only demonstrate the feasibility of MW-level CW conditioning using a TWRR but also establish a test platform for future CEPC high-power component validation and conditioning.

Speaker: 凡予 王 (高能物理研究所)

11:00 [A02] An FPGA Emulator for Superconducting-Cavity LLRF Controller Validation

This paper presents the implementation and open-loop validation of a cavity emulator for the 1.3 GHz pulsed superconducting-cavity LLRF system under development in our group, for which the real cavity will not be available for an extended period. The emulator runs on an AMC-7Z045 board (Xilinx XC7Z045) and executes the cavity, RF-amplifier, coupler, beam, and detuning models as a pipelined fixed-point recurrence, including quench-like abnormal operation. All rate-dependent quantities are derived from a hardware-measured application clock, so the emulated plant retains its physical time scale across model rates from 3.125 to 10 MS/s. Validated on public operating data of a European XFEL cavity, parameters identified from 100 pulses predict 100 held-out pulses with 1.76\% complex and 0.56\% envelope NRMSE; the board reproduces the identified digital model to 0.002\%. A dedicated interface board, designed as a drop-in replacement for the cavity chain at the controller's existing signal interface, provides the converter-level reference plane. The present validation is open-loop; the common-clock controller-in-the-loop experiment through the interface board is specified and will be reported following hardware completion. The results establish that the emulator adds negligible numerical distortion to the validated plant model and can serve as a controlled substitute for controller commissioning before machine access.

Speaker: Wenbin Gao (IHEP, UCAS)

11:00 [A03] Development of high power energy recovery absorbing load for large scale accelerators

For large particle accelerators, the radio-frequency (RF) power source system accounts for a significant portion of total energy consumption. A considerable fraction of the RF power that is not used for particle acceleration is delivered to an absorbing load located at the output of the accelerating structure, where it is converted into heat and dissipated. Recovering this otherwise wasted energy is therefore of great interest for improving the overall energy efficiency of accelerator facilities.
RF-DC rectification technology offers a potential approach to convert the RF power into usable DC electricity. However, the practical implementation of this concept has long been limited by insufficient high-frequency and high-power handling capabilities of conventional semiconductor devices. As a result, although the concept is attractive, it has rarely been demonstrated in experimental or engineering applications at the GHz frequencies.
With the recent development of fourth-generation Gallium Nitride (GaN) transistors, significant improvements in high-frequency and high-power performance have been achieved, making RF energy recovery at microwave frequencies more feasible.. This work investigates the feasibility of a GaN-based RF rectification scheme for high-power energy-recovery absorbing loads in large-scale accelerators.

Speaker: 杨 赵 (中国科学院高能物理研究所)

11:00 [A04] Multibeam Klystron Design for 10 MW L-Band Operation: Simulation Results for the Electron Gun, Focusing system, RF Interaction Structure, Output Window and Collector

This work presents the design and multi-code simulation of a 10 MW-class L-band (1.3 GHz) multi-beam klystron (MBK) intended as a high-efficiency RF power source for superconducting linear accelerators. The design covers the electron gun, magnetic focusing system, RF interaction structure, output window, and collector. Six low-perveance (0.57 μP) beamlets extracted at a cathode voltage of -115.1 kV provide a total space-charge-limited current of 134.8 A, corresponding to a DC beam power of 15.5 MW. The maximum surface electric field is limited to 5.8 kV/mm, approximately 27% below the estimated breakdown limit, while the cathode loading is maintained ~2.0 A/cm² to ensure long cathode life. A ten-coil confined-flow focusing system transports the beam with an average beam radius of 5.1 mm, a magnetic field ripple of 5.0%, and a fill factor of 0.57. The 2D and 3D magnetic field simulations agree within approximately 0.2%. Beam dynamics simulation cross-validated using AJDISK (1D), KlyC (1.5D), and KlyC (2D) predict RF efficiencies of 69–74% and output powers of 10.5–11.3 MW, exceeding the 10 MW design target. The RF output window achieves an S11 of −35.4 dB and a VSWR of 1.034 at 1.3 GHz. Coupled thermal-mechanical analysis gives a peak temperature of 41.4 °C, corresponding to a temperature rise of approximately 16.4 °C, and a maximum von Mises stress of 0.0197 GPa. For the collector, a grooved, double-walled structure reduces the peak surface temperature from 259.6 °C to 183.5 °C under the full 15.5 MW DC beam, demonstrating adequate thermal and structural margins throughout. These results confirm the feasibility of the proposed 10 MW L-band MBK design and provide a comprehensive simulation basis for subsequent prototype fabrication and experimental validation.

Speaker: Mr NOMAN HABIB (IHEP)

11:30 [A05] Coupling Mechanisms of Focusing Magnetic Field, Load Mismatch, and Electron Reflection in High-Power Klystrons

High-power klystrons play a critical role in microwave power amplification in radio-frequency (RF) systems for large-scale accelerators, and their operational stability directly affects the long-term reliability of the RF system. To investigate output-power fluctuations, electron reflection, and parasitic oscillations that may occur under load-mismatch conditions, this study takes the output cavity as the core and establishes a coupled analysis model incorporating the focusing magnetic field, beam transport, complex loading of the output cavity, and feedback from backstreaming electrons. Based on the relativistic equations of electron motion, the effects of the focusing magnetic field on beam transmission and the fundamental-frequency beam current upstream of the output cavity are analyzed. By combining the equivalent-circuit model of the output cavity with transmission-line theory, the relationships among the voltage standing-wave ratio (VSWR), reflection phase, normalized load admittance, equivalent external quality factor, loaded quality factor, and gap voltage are derived. Electron reflection under strong decelerating fields and the corresponding feedback conditions are also discussed. Calculations using the output-cavity parameters considered in this study show that, at a VSWR of 1.2 and with the fundamental-frequency beam current assumed to remain approximately unchanged, different reflection phases can increase the gap voltage by approximately 19.8% or decrease it by approximately 16.5% relative to the matched condition. This indicates that the same VSWR does not necessarily correspond to the same operating state of the output cavity. Therefore, the influence of load mismatch on stability depends jointly on the magnitude and phase of the reflection coefficient, while the focusing magnetic field further affects the risk of electron reflection by modifying beam transport and bunching conditions. These results provide a reference for the selection of output-cavity loading parameters, adjustment of the focusing magnetic field, and determination of protection thresholds against load mismatch.

Speaker: 晓博 周 (高能物理研究所)

11:30 [A06] Lattice Design and Dynamic Aperture Optimization for the BEPCII-UP with Crab Waist Scheme

The BEPCII Upgrade (BEPCII-UP) adopts the crab waist collision scheme to significantly enhance luminosity. In this study, lattice design (including the survey, optics parameters, and working point matching) and dynamic aperture optimization for the BEPCII-UP collider ring are carried out using the SAD code. To obtain a sufficient dynamic aperture for injection, a combined-function magnet scheme (B+S) is explored, and a genetic algorithm is employed to optimize the strengths of the sextupoles. The optimized lattice preliminarily meets the injection requirement on dynamic aperture and improves the beam lifetime compared with the initial design, providing a reliable basis for the BEPCII-UP crab waist scheme.

Speaker: Mingyang Zhao

11:30 [A07] Research on 2D-3D Collaborative Layout for Particle Accelerators

Layout design is a core procedure in particle accelerator development, which guarantees the precise implementation of physics design and underpins full-lifecycle operation and maintenance of the facilities. 2D layout drawings act as fundamental engineering benchmarks for equipment positioning, while 3D layout models provide a global spatial perspective for coordination verification and construction guidance.

Next-generation large-scale scientific facilities, represented by the High Energy Photon Source (HEPS) and the Circular Electron-Positron Collider (CEPC), are evolving toward compact designs with sub-millimeter positioning accuracy. This trend leads to exponential growth in equipment quantity and layout complexity. Nevertheless, the traditional phased manual iteration workflow for layout design has shown critical bottlenecks: isolated 2D and 3D data systems, dependence on manual cross-dimension updates, heavy repetitive workload, and error accumulation during version iterations. These drawbacks make it difficult to meet the high-efficiency design requirements of future ultra-large accelerator facilities.

To address the above issues, this paper proposes a 2D-3D collaborative layout design method. A parametric association model is established to realize bidirectional automatic synchronous updates between 2D and 3D layout deliverables. Furthermore, an intelligent layout algorithm based on physics survey data will be developed, which can automatically identify equipment boundary constraints, achieve accurate device positioning, and synchronously generate 2D and 3D layouts conforming to engineering specifications.

Preliminary verification based on the CEPC booster layout shows that the proposed method reduces manual repetitive drafting work by over 40%, shortens the layout design cycle by more than 30%, and effectively reduces the time cost and human error risk caused by manual operations. This study notably improves the efficiency and accuracy of accelerator layout design, and provides a replicable technical solution for the efficient design and digital upgrading of new-generation large-scale scientific facilities.

Speaker: 思雨 陈 (高能所)

11:30 [A08] Design and Optimization of High-Power, High-Efficiency S-Band Multi-Beam Klystrons for Large-Scale Scientific Facilities

This work presents the design and analytical optimization of a high-power, high-efficiency S-band multi-beam klystron (MBK) intended as an RF power source for large-scale scientific facilities. Existing accelerator klystrons demonstrate $50-80 MW$-class peak power near $2.856 GHz$, whereas established MBKs and recent high-efficiency developments operate in the $60-70\%$ electronic-efficiency range. The present design therefore targets $2.856 GHz$, $50 MW$ peak RF output, $62\% $electronic efficiency, at least $50 dB$ saturated gain, $3-4 μs$ RF pulses at $50-60 Hz$, and at least $99\%$ beam transmission. The design covers the multi-beam electron gun, magnetic focusing system, RF interaction structure, output coupling and window, and collector. The extracted RF power is written as $P_{out}≈ ½I_1 M V_g cos ψ$, giving the electronic efficiency $η_e = P_{out}/(V_0 I_{tot} ) ≈ ½(I_1/I_{tot} )((M V_g)/V_0 ) cos ψ$. This relation identifies the fundamental current ratio, transit-time factor, normalized output-gap voltage, and decelerating phase as the principal interaction parameters. The per-beam microperveance is $K_{(μ,b)} = 10⁶I_{tot}/(N V_0^{3/2} )$, which can be combined with the power balance to obtain $K_{(μ,b)}= 10⁶P_{out}/(N η_e V_0^{5/2} )$. The measured-tube trend $η_{fit} = 100/(1 + 0.79008K_μ )$ is used as a first-pass screen, so beam number and operating voltage are co-optimized to maintain low per-beam perveance without prescribing particular voltage or current values. The RF interaction structure combines staged fundamental bunching, harmonic correction, penultimate bunch shaping, and loaded output extraction. Drift lengths and detuning are adjusted to compress the phase distribution and maximize the fundamental beam-current component at the output gap. The gap geometry follows $M = (sin(θ/2))/(θ/2),θ = ωg/v_0$ , with a target $M ≥ 0.95$. Output loading and magnetic focusing are subsequently matched to the bunched beam, and the design is accepted only when the power, efficiency, gain, and transmission targets are achieved without excessive returning electrons, RF breakdown, or thermal loading. This approach converts demonstrated large-klystron performance into a self-consistent S-band MBK design route for subsequent multi-code simulation and experimental validation.*

Speakers: Sirui Yi (IHEP), Zusheng Zhou (IHEP), Ouzheng Xiao (IHEP)

12:00 [A09] Development of high voltage pulsed modulator for the CEPC C band 80MW Klystron

High-voltage pulse modulator is a key device in linear accelerators, serving as the intermediate link that converts power from the power supply into microwave power. According to the CEPC technical design, the linear accelerator requires 236 sets of C-band 80 MW power source systems to supply 5712 MHz/3 μs/100 Hz pulsed power to the accelerating structures. To achieve the target klystron output power of 80 MW, the high-voltage pulse modulator must deliver pulsed voltages of 425 kV, pulsed currents of 425 A, and a minimum output power of 180 MW. The pulse rise and fall times directly determine the modulator's efficiency, while repetition stability critically influences beam quality. The 100 Hz repetition rate imposes stringent requirements on power handling capacity and thermal management. To meet these challenges, a high-voltage pulse modulator based on a solid-state topology has been developed specifically for C-band 80 MW applications. This paper presents the current development progress from several aspects, including the comprehensive circuit calculation of the high-voltage pulse modulator, theoretical analysis and structural design of the pulse transformer, and simulation analysis.

Speaker: Fei Li (IHEP)

12:00 [A10] Electric Field Gradient Optimization and Multi‑Dimensional Performance Verification of an S‑band 80 MW Klystron Electron Gun Based on NSGA‑II Algorithm

The operating voltage of high‑power klystron electron guns reaches the hundred‑kilovolt level. High electric‑field gradient inside the gun readily causes vacuum breakdown and other adverse phenomena, which degrade the voltage withstand capability and service life of the device. Taking a high‑efficiency klystron electron gun as the research object, this paper adopts the Non‑dominated Sorting Genetic Algorithm‑II (NSGA‑II) multi‑objective genetic algorithm to collaboratively optimize the geometric dimensions of the focusing electrode for electric‑field gradient suppression. Two optimized configurations with different fillet radii for the focusing electrodes are obtained. Subsequently, steady‑state temperature field, thermal deformation and modal oscillation verification are carried out simultaneously. The eigenmodes of the optimized structure are far away from the operating excitation frequency band, and no risk of self‑excited oscillation exists. This research provides a theoretical basis for the low‑electric‑field structural design of similar high‑power klystron electron guns.

Speaker: 宇樱 丁 (高能所)

12:00 [A11] Research on Optimization of On‑site Installation Technology for HEPS Vacuum Equipment

The storage ring vacuum system is a core component ensuring stable beam operation. Its primary function is to provide an ultra‑high‑vacuum environment with ultra‑low gas density for the beam, mitigate scattering losses induced by interactions between the beam and residual gas, and prolong beam lifetime.
The storage ring vacuum system mainly consists of Cr‑Zr‑Cu vacuum chambers, stainless‑steel vacuum chambers, bellows, various vacuum pumps (ion pumps, NEG pumps, etc.), cold cathode gauges and other components. The vacuum chambers adopt a small‑aperture design with an inner diameter of 22 mm and are fabricated from three types of materials, which imposes extremely stringent requirements on installation accuracy, sealing reliability and installation efficiency. Meanwhile, magnets are densely arranged inside the storage ring tunnel with limited operating space. Conventional installation tools and processes cannot meet the high‑precision installation requirements.
This paper systematically summarizes the technical practices for on‑site installation of the HEPS storage ring vacuum system. Aiming at the challenges encountered during installation, including multi‑cycle parallel installation, extremely confined space and stringent alignment accuracy requirements, a procedural installation process scheme is proposed.By optimizing the parallel workflow of three key procedures: vacuum chamber alignment, vacuum equipment installation and vacuum leak detection, developing multiple special non‑standard installation tools, and establishing standardized pre‑installation inspection and process‑control specifications, the efficient installation of vacuum equipment for the 1360.4 m beam line of the storage ring has been realized. After installation, following segmented baking and NEG‑film activation, the average static vacuum level outperforms the design specifications. It provides engineering experience for the on‑site installation of vacuum systems of comparable large‑scale scientific facilities.

Speaker: Tianfeng Liu (IHEP)

12:00 [A12] Design of an S-band 50 MW periodic permanent magnet focused klystron

High-efficiency klystrons can significantly reduce the operational costs of particle accelerators. For the low-duty-factor klystrons commonly used in linear accelerators, however, the power consumption of electromagnetic focusing coils remains non-negligible. This work presents the progress of an S-band 50 MW high-efficiency klystron with periodic permanent magnet (PPM) focusing, aiming at high conversion efficiency while minimizing auxiliary power consumption.

Because of the relatively large dimensions of S-band tubes, the focusing structure is constrained and the beam rigidity is limited. These factors impose stringent requirements on the beam-dynamics design and require coordinated optimization of the magnetic-field configuration and the electron bunching process. Three-dimensional PIC simulations give an output power of 51.2 MW and an efficiency of 53.8%, with no reflected electrons. The overall tube length is 1310 mm.

The proposed S-band PPM klystron provides a promising approach for improving the efficiency and reducing the operational cost of high-power RF sources in accelerator applications.

Speaker: 汉 肖 (高能所)

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