The 2025 International Workshop on the High Energy Circular Electron Positron Collider

5 Nov 2025, 00:00 → 10 Nov 2025, 18:15 Asia/Shanghai

Guangzhou Dongfang Hotel

Hengne Li (South China Normal University) , Jianchun Wang (IHEP) , Miao He (IHEP)

The 2025 International Workshop on the High Energy Circular Electron Positron Collider (CEPC2025) will take place in Guangzhou, November 6-10, 2025, co-hosted by South China Normal University and the Institute of High Energy Physics, CAS.

The CEPC study group has released the Technical Design Report (TDR) on the accelerator and is progressing toward the Engineering Design Report (EDR). Additionally, the group plans to release a TDR for a reference detector in 2025. This workshop aims to bring together scientists worldwide to explore the physics potential of the CEPC, enhance international collaboration on optimizing the accelerator and detectors, and advance R&D on critical technologies. Moreover, discussions on industrial partnerships for technology R&D and industrialization preparation will be included.

The workshop program will feature plenary, parallel, and poster sessions. All plenary presentations will be invited talks, while posters will be selected from submitted abstracts. Parallel session presentations will be drawn from both sources. The workshop encourages participation, particularly from graduate students and postdocs.

Poster presenters, please follow the instructions. Outstanding posters will receive awards, selected by a committee comprising SPC members, session conveners, and local organizers.

For information regarding visa applications, please visit https://indico.ihep.ac.cn/event/20099/, also accessible through the registration page. 

All payments will be handled on-site and any official notices will come from our support email address: cepcws2025@ihep.ac.cn. And the attendance certificate will be posted on indico after the workshop so that you can download it.

Deadline for abstract submission is September 30, 2025. Deadline for registration is October 10, 2025.

For assistance, please contact cepcws2025@ihep.ac.cn.

Attendance Certificate_CN.pdf

Attendance Certificate_EN.pdf

CEPCWS2025Booklet.pdf

Group Photo.jpg

Workshop Announcement_CN.pdf

Workshop Announcement_EN.pdf

Wednesday, 5 November

14:00 → 20:00 Registration

Thursday, 6 November

09:00 → 10:20 Plenary: 1

Zoom Link, ID:93618001420, Code:427946

Convener: Hengne Li (South China Normal University)

09:00 Welcome

Speaker: Enke Wang (South China Normal University)

09:10 Physics opportunities at future e+ e- colliders

Speaker: Jorge de Blas (U)

Physics_Opportunities_Future_ee_Colliders.pdf

09:50 Progress of CEPC accelerator EDR

Speaker: Jie Gao (IHEP)

Progress of CEPC accelerator EDR V1-J. Gao.pdf

Worldwide collider brief history as background materials-Review of different colliders.pdf

10:20 → 10:50 Coffee break and group photo

10:50 → 12:55 Plenary: 2

Zoom Link, ID:93618001420, Code:427946

Convener: Yuanning Gao (Peking University)

10:50 CEPC reference detector TDR

Speaker: Joao Guimaraes da Costa

20251106-Detector-CEPC-Workshop-Guangzhou.pdf

20251106-Detector-CEPC-Workshop-Guangzhou.pptx

11:20 The FCC program

Speaker: Paolo Giacomelli (INFN-Bo)

FCC program-CEPC workshop 2025.key

FCC program-CEPC workshop 2025.pdf

FCC program-CEPC workshop 2025.pptx

11:55 Challenges of the EW precision tests

Speaker: Alessandro Vicini (University of Milano)

Vicini-precisionEW-CEPC2025.pdf

12:25 Flavour physics at future e+e- colliders

Speaker: Lorenzo Calibbi (Nankai University)

calibbi-CEPC-2025.pdf

13:00 → 14:00 Lunch break

14:00 → 15:30 Accelerator: 1

Zoom Link, ID:93618001420, Code:427946

Convener: Maria Enrica Biagini (INFN-LNF)

14:00 CEPC accelerator EDR status

Speaker: Jie Gao (IHEP)

CEPC Accelerator EDR status and Plan-CEPC2025-V1-J. Gao.pdf

14:18 Review of accelerator activities in INFN-Frascati (remotely)

Speaker: Alessandro Gallo

A_Gallo@CEPC2025Wshop.pptx

14:36 CEPC collider ring beam dynamics EDR plan and status

Speaker: Yiwei Wang (IHEP)

EDR Status of the CEPC collider ring beam dynamics (CEPC 2025).pptx

14:54 Correction and tuning strategies for the FCC-ee (remotely)

Speaker: Jacqueline Keintzel (CERN)

15:12 CEPC first tune operation required machine tuning (including orbit corrections and sextupoles with all errors) and luminosity ramping scenarios

Speaker: Bin Wang (IHEP)

20251106_CEPC_workshop_BinWang_v3.pptx

14:00 → 15:30 CIPC: 1

Zoom Link, ID:91076566347, Code:228773

Convener: 王少哲 (昆山国力大功率器件工业技术研究院有限公司)

14:00 超导腔加工制造突破与产业化应用

Speaker: 陈明伦 副总 (宁夏东方超导科技有限公司)

超导腔加工制造突破与产业化应用 -陈明伦- 2025.11.06.pdf

14:20 加速器高频相关部件研制情况汇报

Speaker: 李荣 副总 (安徽海泰科电子科技有限公司)

安徽海泰科电子科技有限公司介绍-20251106YS.pptx

14:40 高功率耦合器研发进展

Speaker: 于凯凯 技术总监 (摩科斯电子科技（苏州）有限公司)

15:00 安徽华东光电-大科学装置配套项目介绍

Speaker: 吴磊 事业部部长 (安徽华东光电技术研究所有限公司)

安徽华东光电汇报材料-2025.11.pptx

14:00 → 15:40 Higgs: 1

Zoom Link, ID:96812316331, Code:367916:

Convener: Wei Su (Sun Yat-Sen University)

14:00 Electroweak Corrections to Higgs boson production and decay

I present the calculation of complete next-to-leading order electroweak corrections to the Higgs boson production in $gg\to g H$ channel as well as it's rare decay.
We apply the method of differential equations combined with the selection of optimized master integrals to accomplish the calculation of master integrals. We consider three distinct renormalization schemes.
At leading order, the differential distributions and the total cross section show a strong dependence on the renormalization scheme. However, these discrepancies are considerably suppressed once electroweak corrections are taken into account. For $G_\mu$ scheme, the electroweak correction amounts to approximately $4.3\%$ of the total cross section. Importantly, {\color{red} we find that the EW corrections exhibit a strong dependence on Higgs transverse momentum.

Speaker: Longbin Chen (University of Guangzhou)

Higgs-EW-LBC.pptx

14:20 Discovery Potential of Future Electron-Positron Colliders for a 95 GeV Scalar

Speaker: Bruce Mellado or Andreas Crivellin

95GeVatCEPC.pdf

14:40 Search for Dark Matter in 2HDMS at LHC and future Lepton Colliders

Speaker: Juhi Dutta, Jayita Lahiri, Cheng Li, Gudrid Moortgat-Pick, Sheikh Farah Tabira, Julia Anabell Ziegler

2HDMS_coll_LCH.pdf

15:00 Searching for leptophilic composite asymmetric dark sector at e+e− colliders

Composite asymmetric dark matter (ADM) models provide a well-motivated paradigm that simultaneously explains dark matter (DM) relic density and matter-antimatter asymmetry. In these models, the mass of the DM candidate (the lightest dark baryon) is generated through the dark confinement scale dynamics. Although the leptophilic composite ADM model offers a viable framework, comprehensive studies of its collider phenomenology are absent. This work systematically explores novel signatures from leptophilic composite asymmetric dark sector at both low-energy and high-energy $e^+e^-$ colliders as well as other existing collider constraints. We demonstrate detectability of TeV-scale mediators along with sub-GeV to GeV-scale lightest dark mesons at Belle II and its proposed far detector, GAZELLE, as well as CEPC experiments. Moreover, these experiments exhibit complementary coverage of the model parameter space.

Speaker: Changbin Xi (南京师范大学物理科学与技术学院)

Searching for leptophilic composite asymmetric dark sector at e+ e- colliders_Changbin-Xi_1105.pdf

15:15 The electroweak precision constraints of the 2HDM+S

Speaker: Ms Juxiang Li (SYSU)

The electroweak precision observables of the 2HDM+S.pdf

14:00 → 15:30 Silicon Detector: 1

Zoom Link, ID:97990003364, Code:309122

Convener: 梁志均 LIANG Zhijun

14:00 Overview of the CEPC Vertex Detector

Speaker: Ying Zhang (IHEP)

CEPC-Vertex_Overview_20251106_f.pdf

14:22 CEPC Silicon Tracker Detector

The CEPC Silicon Tracker, comprising the Inner Silicon Tracker (ITK) and Outer Silicon Tracker (OTK), will cover a total active area of approximately 100 m². It integrates advanced pixel sensors for the ITK and microstrip sensors for the OTK, with micron-level precision to achieve per-mille-level momentum resolution, measuring charged-particle trajectories from below 1 GeV/c to above 100 GeV/c. The detector will also serve as a high-precision Time-of-Flight system, targeting a single-layer timing resolution of 50 ps. By combining high-performance sensors, electronics, mechanics, and cooling, the design of the reference detector for the CEPC has been finalized, and the corresponding R&D work is ongoing. This presentation provides a comprehensive overview of the detector design, as well as the current status and future plans for system development.

Speaker: Qi YAN (IHEP)

CEPCWorkshopSTK202511V2.pdf

14:44 CIS sensor prototyping with Chinese foundry

Speaker: Dr Xiangming Sun (CCNU)

ClS sensor prototyping with Chinese foundry.pptx

15:06 HV-MAPS for the Mighty-Tracker of the upgraded LHCb detector

Speaker: Sebastian Bachmann (University of Heidelberg)

20251105_CEPC.pdf

15:30 → 16:00 Coffee break

16:00 → 18:35 Accelerator: 2

Zoom Link, ID:93618001420, Code:427946

Convener: Frank Zimmermann (CERN)

16:00 Accelerator activities in Korea University

Speaker: Eun-san Kim

16:20 Accelerator activities in CEA

Speaker: Pierre Vedrine

16:40 CEPC Magnets (both collider & booster)

Speakers: Mei Yang, Wen Kang (Accelerator Centor, IHEP)

CEPC Magnets (both collider & booster)-20251106.pptx

17:00 Ivan Karpov (CERN), FCC RF operation scenarios - new baseline(remotely)

Speaker: Ivan Karpov (CERN)

17:20 Radiation in the tunnel and its mitigation for CEPC EDR（Remotely）

Speaker: Guangyi Tang (IHEP)

CEPC workshop 2025.pptx

17:40 Strategy for mitigating radiation to equipment in FCC-ee（remotely）

Speaker: Anton Lechner

FCCee_radshield_06112025_v1.pdf

16:00 → 18:20 CIPC: 2

Zoom Link, ID:91076566347, Code:228773

Convener: 李荣 (安徽海泰科电子科技有限公司)

16:00 P波段大功率速调管国力研制情况介绍

Speaker: 王少哲 研究院副院长 (昆山国力大功率器件工业技术研究院有限公司)

2025 CIPC分会-P波段大功率速调管国力研制情况介绍.pdf

16:20 超高幅相稳定度固态放大器

Speaker: 何圣侃 总经理 (无锡市华康广播电视设备厂)

CEPC-2025无锡市华康广播电视设备厂.pptx

16:40 高能物理领域高压电缆及组件介绍

Speaker: 杨德亮 市场部长 (江苏创仕澜传输科技有限公司)

高压电缆及组件介绍CEPC年会-.pptx

17:00 大功率脉冲速调管汉光研制情况介绍

Speaker: 米伟光 真空电子事业部部长 (湖北汉光科技股份有限公司)

大功率脉冲速调管汉光研制情况介绍.pptx

17:20 固态调制器在直线加速器上的应用

Speaker: 白亚鑫 经理 (北京大有科能科技有限公司)

固态调制器应用-.pptx

17:40 液氦低温抗辐射微波元器件简介

Speaker: 朱云川 总经理 (江苏安胜达航天科技股份有限公司)

液氦低温抗辐射微波元器件简介—安胜达航天.pptx

16:00 → 18:00 Higgs: 2

Zoom Link, ID:96812316331, Code:367916:

Convener: Mingshui CHEN (IHEP)

16:00 Measurement of the Higgs decaying into two photons with the CEPC reference detector

This presentation details a study of the prospective measurement of the cross-section times branching ratio for Higgs decaying into two photons, $\sigma(e^{+}e^{-} \rightarrow ZH) \times \mathrm{Br}(H \rightarrow \gamma\gamma)$, at the Circular Electron Positron Collider (CEPC). The analysis is performed at a center-of-mass energy of $\sqrt{s} = 240$ GeV, considering the three dominant $Z$ boson decay channels: $Z \rightarrow q\bar{q}$, $\mu^{+}\mu^{-}$, and $\nu\bar{\nu}$. Using simulated Monte Carlo events corresponding to an integrated luminosity of $21.6~\text{ab}^{-1}$, a combined statistical precision of $3.1\%$ is achieved. Furthermore, we investigate the impact of the electromagnetic calorimeter (ECAL) performance by studying the degradation of the photon energy resolution. Our results indicate that the stochastic term is the dominant factor, and a transition from a Silicon-Tungsten to a glass bar ECAL design significantly improves the energy resolution, thereby enhancing the precision of the $H \rightarrow \gamma\gamma$ measurement.

Speaker: Mr Reda Mekouar (高能所)

Measurement_of_the_Higgs_decaying_into_two_photons_with_the_CEPC_reference_detector.pdf

16:20 Search for long-lived particles in the Higgs decays with the CEPC reference detector

Speaker: Xiang Chen, Liang Li

cepc_workshop_251106_v1.pdf

16:40 CP violation in Higgs to tautau decays at CEPC

It is not excluded by the LHC experiments that the SM-like Higgs boson is a mixture of CP eigenstates of opposite parities. In such a scenario, the mixing angle can be measured at CEPC in Higgs to tau-pair decays. We present a preliminary result of the mixing angle measurement obtained with the fast simulation of the CEPC detector.

Speaker: Ms Ivana Vidakovic (VINCA Institute of Nuclear Sciences)

CP violation in Higgs decay to tautau at the CEPC.pdf

17:00 Measurement of the Higgs mass with the CEPC reference detector

Speaker: Chenguang Zhang (IHEP,Beijing)

H_recoil_20251106_guangzhou.pdf

17:20 Search for the invisible decay of the Higgs boson with the CEPC reference detector

Speaker: Geliang Liu (Laboratoire Leprince-Ringuet, École Polytechnique)

20251106_CEPCWorkshop_Hinvi_GeliangLiu.pdf

17:40 Analytical calculation of multi-loop Feynman integrals with masses

Embed in Grassmannians, we can obtain the analytical hypergeometric function solutions of multi-loop Feynman integrals with masses. We can make the classification among those hypergeometric solutions by geometric configurations. We can generalize Gauss relations among the hypergeometric functions to complete analytic continuation of the solutions. This method can be applicable to the high-order corrections of physical quantities in future high-precision colliders.

Speaker: Prof. Haibin Zhang (Hebei University)

Analytical calculation of multi-loop Feynman integrals with masses.pdf

16:00 → 18:05 Silicon Detector: 2

Zoom Link, ID:97990003364, Code:309122

Convener: Harald Fox (Lancaster University)

16:00 CASSIA - First results of a Monolithic Active Pixel Sensors with Internal Signal Gain

Speaker: Heinz Pernegger (CERN)

CASSIA-CEPC-November2025.pdf

16:25 Serial powering and its implementation in the ATLAS ITk detector

Speakers: Florian Hinterkeuser (Uni Bonn) , Florian Hinterkeuser (Universität Bonn)

SerialPowering_ATLAS_CEPC2025.pdf

16:50 Module Developments with ATLASPix3

Speakers: Fuat Ustuner (The University of Edinburgh) , Sebastian Bachmann (University of Heidelberg)

FU_CEPC2025_Workshop_Nogif.pdf

17:15 The ITS3 detector and its physics potential for the LS3 ALICE upgrade

Speaker: Chunzheng Wang (Fudan University)

slides_ITS3_CEPC2025_chun.pdf

17:40 Status and plans of the ARCADIA HV-MAP sensors

Speakers: Manuel Da Rocha Rolo (INFN) , Manuel Dionisio Da Rocha Rolo (INFN Torino) , Manuel Rolo (CERN)

20251106_ARCADIA4CEPC.pdf

19:00 → 21:00 Plenary: Public lecture

Zoom Link, ID:93618001420, Code:427946

19:00 希格斯与中微子：通向粒子物理未来的两个窗口

Speaker: Yifang Wang (高能所)

PublicLecture_251106.png

Friday, 7 November

09:00 → 10:30 Accelerator: 3

Zoom Link, ID:93618001420, Code:427946

Convener: Jie GAO (IHEP)

09:00 KEK super B status and international collaborations (remotely)

Speaker: Makoto Tobiyama (KEK Accelerator Laboratory)

SuperKEKB_CEPC2025_tobiyama.pdf

09:18 IHEP-KEK collaboration on Super KEK B beam-beam effects

Speaker: Chuntao Lin

IHEP-KEK collaboration on SuperKEKB beam-beam effects.pptx

09:36 Super KEK B injection related issues (Remotely)

Speaker: Meng Li

CEPCworkshop_2025-11-7.pdf

09:54 CEPC booster and damping ring (DR) EDR plan and status

Speaker: Dou Wang (IHEP)

wangd-v2.pptx

10:12 CEPC Linac EDR plan and status

Speakers: Cai Meng (高能所) , Jingru Zhang (IHEP)

Linac EDR 2025 workshop.pptx

09:00 → 10:40 CIPC: 3

Zoom Link, ID:91076566347, Code:228773

Convener: 张玉包 (北京高能新技术有限公司)

09:00 Accelerating Equipment Development at IHEP&HERT

Speaker: 郭润兵/张占军 副总经理 (北京高能锐新科技有限责任公司)

Accelerating Equipments Development at IHEP&HERT 2025-.pdf

09:20 近年国内低温装置的进展

Speaker: 高金林 总经理 (中科富海低温科技有限公司)

近年国内低温装置的进展-jlg v1.pdf

09:40 大科学装置中的关键低温装备研究

Speaker: 孙大明 教授 (浙江大学，浙江紫明低温科技有限公司，江苏克劳特低温技术有限公司)

大科学装置中的关键低温装备研究-浙江大学&浙江紫明低温科技.pdf

10:00 真空阀门应用

Speaker: 刘长江 营运副总经理 (日扬电子科技（上海）有限公司)

日扬 CEPE简介.pptx

10:20 普发产品在加速器上的应用

Speaker: 刁立臣 经理 (北京世华尖锋科技有限公司)

普发产品在加速器领域的的应用和质谱仪的国产化- CEPC.pdf

09:00 → 10:45 Higgs: 3

Zoom Link, ID:96812316331, Code:367916:

Convener: Ke-Pan (柯盼) Xie (谢) (Beihang University (北京航空航天大学))

09:00 Chasing 2HDM via electroweak corrections at e+e- colliders

In this talk, I will present a comprehensive study of Higgs boson production associated with a neutrino pair at $e^+ e^−$ colliders ($e^+ e^- \to h \nu \bar{\nu}$) at NLO electroweak (EW) accuracy in both the SM and the two-Higgs-doublet model (2HDM). I will show that new physics effects from the extended Higgs sector can be probed through EW corrections, which lead to deviations from the SM predictions reaching 6% to 7%. Even in the alignment limit, these deviations can still reach 2% to 3%, making them experimentally testable. This highlights the potential of precision studies at future $e^+ e^−$ colliders for searching new physics.

Speaker: Dr Hantian Zhang (CERN)

2HDM_CEPC25_Zhang.pdf

09:20 Highlights of the HL-LHC physics projections by ATLAS and CMS

The ATLAS and CMS experiments are unique drivers of our fundamental understanding of nature at the energy frontier. In this contribution to the update of the European Strategy for Particle Physics, we update the physics reach of these experiments at the High-Luminosity LHC (HL-LHC) in a few key areas where they will dominate the state-of-the-art for decades to come.

Speaker: Chen Zhou (Peking University)

CEPC_20251107_HL-LHC.pdf

09:40 Testing a light Higgs of 95 GeV at CEPC

Several excesses around 95 GeV hint at an additional light scalar beyond the Standard Model. We examine the CEPC's capability to test this hypothesis via the Higgsstrahlung channel $e^+e^-\to ZS$ ($Z\to\mu^+\mu^-$, $S\to\tau^+\tau^-/b\bar{b}$). Our results show that a 210 GeV CEPC run with deep neural networks robustly probes the 95 GeV excess, covering large model parameter spaces. We also discuss future hadron colliders (HL-LHC, HE-LHC, FCC-hh, SppC) for contrast, and use representative models (MDM, Type-I 2HDM, flipped N2HDM, NMSSM) to illustrate these colliders' reach.

Speaker: Prof. Jingya Zhu (Henan University)

JingyaZHU_20251107_CEPC2025.pdf

10:00 FCC-ee Higgs summary

The Future Circular Collider (FCC) is a post-LHC project presenting unparalleled opportunities to thoroughly examine Higgs properties. The electron-positron stage of FCC (FCC-ee), featuring operation modes at 240 and 365 GeV, will produce millions of Higgs bosons through the ZH and VBF processes. Benefiting from the clean experimental environment and the precisely known center-of-mass energy, model-independent measurements of the ZH cross-section and total Higgs width can be performed at per-mil precision. Utilizing the recoil-mass technique, the Higgs boson mass will be measured with a precision of a few MeV. With the efficient particle reconstruction and flavor tagging performance, Higgs couplings to quarks and gluons can be probed with sub-percent to percent precision. This talk summarizes the prospects of Higgs physics at FCC-ee.

Speaker: Dr Xunwu Zuo (EPFL)

FCC-ee Higgs summary 2025.11.07.pdf

10:20 Testing Higgs $CP$ properties at the CEPC with an additional ISR correction parameter.

We evaluate the experimental sensitivity to the $CP$-odd admixture in the standard Higgs boson in the process $e^+e^- \to HZ$, which is expected at future lepton collider CEPC with $\sqrt{s}=240~\text{GeV}$ and statistics of $5.6~\text{ab}^{-1}$. Using the Whizard generator with Higgs Characterisation model and DELPHES detector simulation framework we obtain data samples with different $CP$-odd Higgs admixture parameters $\tilde{c}_{ZZ}$. The initial state radiation (ISR) effects are taken into account in Whizard. Angular and ISR energy shift distributions are used to distinguish the $CP$-odd and $CP$-even Higgs components. Upper limits on the $CP$-odd Higgs admixture parameter are obtained.

Speaker: Mr Egor Vasenin (LPI)

Vasenin_H_CP_CEPCWS_25.pdf

09:00 → 10:30 Silicon Detector: 3

Zoom Link, ID:97990003364, Code:309122

Convener: 梁志均 LIANG Zhijun

09:00 Exploratory Development of 55nm HV-CMOS Pixel Sensors: Design of the COFFEE Series Chips

High-Voltage CMOS (HV-CMOS) pixel detectors, with excellent radiation hardness and fast signal collection enabling nanosecond-level timing and micron-level spatial resolution, are chosen as the baseline for the CEPC Inner Silicon Tracker. Our R&D using a 55 nm process has produced the COFFEE series of prototype chips. Following verification with COFFEE2, the COFFEE3 chip was designed and submitted for tape-out in spring 2025. COFFEE3 implements two readout architectures: one digitizes within each pixel and transmits data in parallel to the array bottom for time stamping, while the other uses a pixel-level Time-to-Digital Converter (TDC) with column-level readout. Both aim for sub-5 ns timing, optimized differently for hit-rate handling and power. This talk will present the COFFEE series R&D, the COFFEE3 design and performance, preliminary test results, and future plans.

Speaker: Yang Zhou (IHEP)

55nmHVmaps_2025_11_CEPC_workshop_YangZhou.pdf

09:20 Studies of AC-coupled Low Gain Avalanche Detector for the CEPC Outer Tracker System

AC-coupled Low Gain Avalanche Detectors (AC-LGADs) have become leading contenders for upcoming 4D tracking systems, attracting considerable interest from numerous research organizations. These detectors have been selected as the Outer Tracker (OTK) detectors for the Circular Electron Positron Collider (CEPC), as the detector can provide both high-precision spatial resolution (∼10 µm) for momentum measurement and high-precision timing (∼ 50 ps) for particle identification. Research on AC-LGADs developed by the Institute of High Energy Physics (IHEP), featuring 5.65-mm-long strip sensors, has shown impressive results, with a timing resolution of about 40 picoseconds and a spatial resolution of approximately 10 micrometers. Total Ionizing Dose (TID) radiation studies have further indicated that these sensors maintain strong performance under CEPC's radiation conditions. Towards CEPC OTK system, An AC-LGAD with a strip length of ~4 cm has been designed, and its performance be evaluated. This presentation includes simulations of AC-LGAD design parameters, including n+ layer dose, isolation structures and so on, with a focus on capacitance optimization aimed at enhancing performance. The design of IHEP's AC-LGAD strip sensors and the preliminary testing results of AC-LGAD sensors with long strips will also be reported.

Speaker: Mei Zhao (高能所, IHEP)

Studies of AC-coupled Low Gain Avalanche Detector for the CEPC Outer Tracker System-MZ-1107.pdf

09:40 Status and plans for the DRD3 collaboration

Speaker: Xin Shi (IHEP)

DRD3-Status-CEPC2025v3.pdf

10:10 Study of Irradiation-Induced Defects in PINs and LGADs by DLTS

Low Gain Avalanche Detectors (LGADs) exhibit excellent properties, including ultra-fast time resolution and a high signal-to-noise ratio. They are widely used in high-energy physics experiments for precise particle detection and time-of-flight measurements. However, irradiation introduces deep-level defects and causes detector performance degradation. Therefore, improving the radiation hardness of LGADs is essential. In this work, capacitance-transient deep-level transient spectroscopy (c-DLTS) and current-transient deep-level transient spectroscopy (i-DLTS) were employed to investigate PINs and LGADs under various neutron and proton irradiation fluences. The defect parameters, including activation energies, capture cross sections, and concentrations, were analyzed. The results show that, compared with i-DLTS, c-DLTS is more sensitive to shallow-level defects. However, at high irradiation fluences, due to increased leakage current and device degradation, c-DLTS may fail to detect defects, while i-DLTS can still reveal typical deep-level defects (e.g., CiOi). Furthermore, under the same irradiation fluence, PINs can resolve both shallow- and deep-level defects, whereas shallow-level defects are hardly observable in LGADs. This phenomenon may be attributed to the gain-layer structure and electric-field effects. Therefore, PINs can serve as a reference for shallow-level defects in LGADs. With increasing irradiation fluence, the variety of observable defects increases, and the concentrations of specific defects (e.g., CiOi and BiOi) rise significantly. Both BiOi and CiOi are directly or indirectly related to the acceptor removal phenomenon, which further accelerates gain degradation in LGADs. The quantitative correlation of these defect concentrations thus provides important guidance for designing radiation-hard LGADs.

Speaker: Wei Li (The Institute of High Energy Physics of the Chinese Academy of Sciences)

20251107_Wei_LI_1.4.pdf

10:30 → 11:00 Coffee break

11:00 → 12:52 Accelerator: 4

Zoom Link, ID:93618001420, Code:427946

Convener: Yeon Sei Chung (IRIS/IBS)

11:00 An overview of the collider activities at IN2P3

Speaker: Angeles Faus-Golfe (fausgolf@ijclab.in2p3.fr)

TUYD1_talk.pptx

11:18 CEPC IP tunning

Speaker: Yuanyuan Wei (IHEP)

CEPC IP tuning (for CEPC workshop)-upload.pptx

11:36 CEPC ground motion

Speaker: Fang YAN (高能所)

yanfang CEPC ground motion.pptx

11:55 CEPC accelerator instrumentation EDR plan and status

Speaker: Yanfeng Sui (高能所)

CEPC accelerator instrumentation EDR plan and status -20251105.pptx

12:15 CEPC Vacuum system EDR plan and status

Speaker: Yongsheng Ma (高能所)

CEPC Vacuum system EDR plan and status.pptx

11:00 → 12:30 CIPC: 4

Zoom Link, ID:91076566347, Code:228773

Convener: 郭润兵 (高能锐新公司)

11:00 项目过程虚拟仿真研究综述与CEPC相关进展 （remotely）

Speaker: 王佳斌 教授 (华侨大学)

CEPC过程仿真研究进展报告.pptx

11:20 北京高能新技术有限公司的发展与技术特点

Speaker: 张玉包 总经理 (北京高能新技术有限公司)

11:40 企业屏蔽防护项目简述及展望

Speaker: 刘小栋 经理 (宜兴市日森防辐射设备有限公司)

企业屏蔽防护项目简述及展望-.pptx

12:00 厦钨集团BGO闪烁晶体项目研发现状及＂十五五＂规划 Current R&D Status and the 15th Five-Year Plan of BGO Scintillation Crystal Project in XTC Group

Speaker: Ms 蔡妙玲 (厦门钨业股份有限公司)

厦钨集团BGO闪烁晶体项目研发现状及＂十五五＂规划.pptx

11:00 → 12:30 Flavor: 1

Zoom Link, ID:96812316331, Code:367916:

Convener: Shanzhen Chen (高能所（IHEP, CAS）)

11:00 Recent LHCb flavor physics highlights

Speaker: Jiesheng Yu (湖南大学)

LHCb_Highlight.pdf

11:25 Recent Belle II flavor physics highlights and future prospects

Speaker: Sen Jia (Southeast University)

Belle2.pdf

11:50 BESIII flavor physics highlights

Speaker: Shuangshi Fang (IHEP)

BESIII-highlight-CEPC-v3.pdf

11:00 → 12:30 Silicon Detector: 4

Zoom Link, ID:97990003364, Code:309122

Convener: Hongbo Zhu (Zhejiang University)

11:00 Results and status of Timepix4 for imaging

Speaker: Hongbin Liu (IHEP)

11:22 CEPC Vertex Detector Mechanics and Cooling

Speaker: Jinyu Fu (高能所)

VTX-mech-cooling-1107GZ.pdf

11:44 Mechanical Design and Future Prospects for the CEPC Silicon Tracker

The CEPC silicon tracker (ITK and OTK) will cover a large sensor area of approximately 100 m². Achieving high performance requires minimizing the material budget while ensuring high structural strength and efficient cooling—a particular challenge for this large and sophisticated tracking system. This report presents the detailed mechanical and cooling design of the CEPC silicon tracker detectors, along with the planned R&D toward a prototype detector.

Speaker: Yujie Li

Mechanical Design and Future Prospects for the CEPC.pdf

12:30 → 14:00 Lunch break

14:00 → 15:30 Accelerator: 5

Zoom Link, ID:93618001420, Code:427946

Convener: Angeles Faus-Golfe

14:00 CEPC impedance budget update in EDR (including collimators) and limitation to luminosities

Speaker: Na Wang (高能所)

CEPC impedance budget update in EDR (including collimators) and limitation to luminosities_NaWang.pptx

14:18 Main rings impedance budget (remotely)

Speaker: Carlo Zannini

14:36 Impact of Collimators' Geometric Impedance on Beam Stability in the FCC-ee (remotely)

Speaker: Dora Gibellieri (CERN)

14:54 CEPC electron cloud effects

Speaker: Yudong Liu

The Electron Cloud and SEY measurents for CEPC-liuyd.pptx

14:00 → 15:30 Calorimetry: 1

Zoom Link, ID:97990003364, Code:309122

Convener: Roberto Ferrari (INFN-PV)

14:00 CEPC Crystal Calorimeter: R&D status and highlights

Precise jet energy reconstruction at the Circular Electron Positron Collider (CEPC) requires an advanced calorimetry system. A novel design for a particle-flow-oriented, high-granularity electromagnetic calorimeter (ECAL) has been proposed, featuring orthogonally layered crystal bars with silicon photomultiplier (SiPM) readout and a target energy resolution of $2\text{-}3\%/\sqrt{E\ (\mathrm{GeV})}\oplus1\%$. After a three-year development and test cycle, a physics prototype with dimensions of $12\times12\times26\ \text{cm}^3$ (~$25\,X_0$) has been constructed. This prototype employs 12 layers of BGO crystals alongside 2 layers of BSO crystals, the latter introduced as a cost-effective alternative and tested for the first time in this configuration. Beam tests conducted at the CERN low-energy T9 and H2 beamlines have been used to characterize its electromagnetic performance. This work provides critical benchmarks and insights for optimizing the crystal ECAL for the CEPC detector.

Speaker: Baohua Qi (IHEP)

20251107_CEPC Crystal Calorimeter R&D Progress and Highlights.pdf

14:30 Study on the Dynamic Range of SiPMs with High Pixel Densities

The future Circular Electron-Positron Collider (CEPC) is a large-scale experimental facility, which aims to accurately measure the Higgs boson, electroweak physics and the top quark. For the detector system in CEPC, a highly granular crystal electromagnetic calorimeter is proposed to achieve an EM energy resolution of less than 3%. It is a homogenous structure with long crystal scintillator bar as active material, and SiPM as the preferred photon sensor. There is a high requirement on the dynamic range of SiPM, since more than half million photoelectrons can be measured for one channel. However, the calibration for SiPMs with such a large dynamic range is challenging. We have explored a series of methods to measure the nonlinear behavior of SiPMs with extremely high pixel densities—25 μm, 10 μm and 6 μm pixel size—under different conditions.

Firstly, using a laser as the light source and a PMT as an auxiliary calibration device, we measured the SiPM response when the pixels are not repeatedly fired. The results from different SiPMs show that under these conditions, the maximum number of photoelectrons measurable by the SiPM approaches its intrinsic pixel number, and nonlinearity becomes apparent when the signal exceeds 10% of the intrinsic pixel number.

Furthermore, we designed a beam experiment to investigate the nonlinearity of SiPMs when measuring intense scintillation light signals. In this case, the decay time of the scintillator is longer than the pixel recovery time of the SiPM, allowing SiPM pixels to be fired multiple times within a single event. We used tungsten plates as a pre-shower and increased the incident angle of the beam particles to enhance the energy absorbed by the crystal unit. Taking advantage of the dual-ended readout of the crystal, we added an optical filter to one end of the crystal to calibrate the actual absorbed energy. Finally, we observed energy absorption in the crystal exceeding 80 GeV as well as the nonlinear response of the SiPM.

Speaker: Zhiyu Zhao (TDLI/SJTU)

20251107_SiPM_nonlinearity_v3.pdf

15:00 An SiW-ECAL for the Future Circular Colliders

A highly granular Silicon-Tungsten ECAL is a way to obtain a high precision for a broad range of conditions and final states. An advanced model has been developed for the Linear Colliders. We will present the progress toward its adaptation for circular colliders: ASICs, timing, power, cooling, optimisation and final state reconstruction.

Speaker: Dr Vincent Boudry (Laboratoire Leprince-Ringuet, CNRS/IN2P3, École polytechnique)

2025-11-07@CEPCWS_SiW-4-Future-Higgs-Factories_VBY.pdf

14:00 → 15:30 Flavor: 2

Zoom Link, ID:96812316331, Code:367916:

Convener: Shuangshi Fang (IHEP)

14:00 FCC-ee future flavor physics perspective

Speaker: Dr Xunwu Zuo (EPFL)

FCC-ee flavor physics perspective 2025.11.07.pdf

14:25 HL-LHCb flavor physics perspective

Speaker: Xuhao Yuan (IHEP, Beijing)

14:50 STCF flavor physics opportunities

Speaker: Cong Geng (Sun Yat-Sen (Zhongshan) University)

STCF-CEPC2025-GC - 2.pdf

14:00 → 15:30 Industrial Connection: 1

Zoom Link, ID:91076566347, Code:228773

Convener: Guoming Liu (South China Normal University)

14:00 All-in-one Solution for Signal Cable Systems

Speaker: 张晓杰 (哈伯思特（北京）电子科技有限公司)

哈伯思特产品介绍CEPC ENGLISH.pptx

14:15 赋能 CEPC 超高真空系统建设：核心零部件的研发、生产和定制化服务

Speaker: 刘长江 (日扬电子科技（上海）有限公司)

20251107 CEPE简介.pptx

14:30 基于开放式FPGA的数字化仪开发

Speaker: 陈龙 (北京中检维康电子技术有限公司)

Digitizer 2.0_2025_lite.pptx

14:45 力科示波器的高速高精度信号测试解决方案

Speaker: 王博 (华特力科(北京)商贸有限公司)

高能物理中的高速高精度信号测试解决方案_Teledyne LeCroy.pptx

15:00 晶垚科技：打造世界级半导体一站式解决方案平台

Speaker: 徐竞为 (晶垚科技(深圳)有限公司)

一站式服务简介_晶垚 -20250722_英文版.pdf

15:30 → 16:00 Coffee break

16:00 → 18:00 Accelerator: 6

Zoom Link, ID:93618001420, Code:427946

Convener: Wei Lu (IHEP)

16:00 Accelerator activities in IRIS/IBS, Korea

Speaker: Yeon Sei Chung (IRIS/IBS)

CEPC2025-Accelerator Activities in IBS.pdf

CEPC2025-Accelerator Activities in IBS.pptx

16:20 A forward looking strategical view on SRF technologies (remotely)

Speaker: Carlo Pagani (INFN-MI)

Pagani_Strategical View on RFTechnology_CEPC2025.pdf

16:40 CEPC SRF (both collider & booster) EDR plan and status

Speakers: Jiyuan Zhai (IHEP) , Peng Sha (高能所)

CEPC SRF EDR plan and status.pptx

17:00 CEPC cryogenic system EDR plan and status (remotely)

Speakers: Mei Li, Rui Ge (IHEP)

CEPC Cryogenic System EDR Plan and Status【2025 CEPC Workshop, GuangZhou】-V3 .pptx

17:20 Status of HALHF (remotely)

Speaker: Brian Foster (University of Oxford)

HALHF_Guangzhou_1125.pptx

17:40 IHEP plasma test facility physics design

Speaker: 诗宇 周

IHEP plasma test facility physics design.pdf

16:00 → 18:00 Calorimetry: 2

Zoom Link, ID:97990003364, Code:309122

Convener: Dr Yong Liu (Institute of High Energy Physics)

16:00 (Semi) Digital Hadron Calorimeter

Speaker: Imad LAKTINEH (IPNL)

16:30 Glass Scintillator Hadron Calorimeter

Speaker: Sen Qian (高能所)

20251106_GSHCALStatus_V3.2.pdf

17:00 Development of a new calorimetry with high-granularity, dual-readout and excellent timing -- Energy resolution evaluation by simulation --

Particle flow algorithm (PFA) and dual-readout are advanced calorimeter technologies proposed for precise jet energy measurements at future colliders. PFA requires highly granular calorimeters for efficient particle separation and optimal energy reconstruction depending on particle type. Dual-readout improves hadronic energy resolution by incorporating both scintillation and Cherenkov detectors, enabling event-by-event identification of the electromagnetic fraction within hadronic showers. Integrating these two technologies into a single calorimeter system poses significant challenges, as conventional dual-readout systems often rely on optical fibers, which are incompatible with the fine segmentation required by PFA. This study explores a novel approach to realize such a hybrid calorimeter by introducing tile-segmented Cherenkov layers into a calorimeter system used at Higgs factory. The expected improvement in energy resolution, achieved by combining these technologies, is evaluated through detailed simulation studies and will be presented in this conference.

Speaker: Kamiyama Taiki (The University of Tokyo)

CEPCWS2025_Taiki.pdf

17:30 Dual-readout crystal calorimeter

Speaker: Marco Lucchini (INFN & University of Milano-Bicocca)

25_10_07_CEPC2025WS_DualReadoutCrystalCalorimeter_.pdf

16:00 → 18:10 Flavor: 3

Zoom Link, ID:96812316331, Code:367916:

Convener: Lorenzo Calibbi (Nankai University)

16:00 b-hadron FCNC decays as a probe of light Dark Matter

Speaker: Xingbo Yuan (Central China Normal University)

slides.pdf

16:25 Prospect for Measurement of CKM Angle $\gamma$ in $B_s^0 -> D_s^{\mp} K^{\pm}$ Decays at CEPC

Prospect for Measurement of CKM Angle $\gamma$ in $B_s^0 \rightarrow D_s^{\mp} K^{\pm}$ Decays at CEPC

Speaker: Yulong Tang

CEPC_CKMgamma_Bs2DsK.pptx

16:50 CKM determination from W decays with Jet tagging at CEPC

We present a study projecting the sensitivity of measuring Cabibbo–Kobayashi–Maskawa (CKM) matrix elements at the CEPC, via direct observation of semi-leptonic WW decays at a center-of-mass energy (\sqrt{s} = 240\ \text{GeV}). This analysis focuses on determining six CKM matrix elements, including (|V_{cd}|), (|V_{cs}|), (|V_{cb}|), (|V_{ud}|), (|V_{us}|), and (|V_{ub}|), and further enables tests of CKM unitarity. By employing state-of-the-art jet flavor taggers, we assess the expected measurement precision. Our results indicate that the CEPC has the potential to significantly enhance the sensitivity to (|V_{cs}|) and (|V_{cb}|), while also providing constraints on the full set of six matrix elements and enabling rigorous tests of their unitarity. However, the achievable performance is found to strongly depend on the level of systematic uncertainties related to the parameters of flavor taggers.

Speaker: Mr Zhaoling Zhang (Jilin University)

CEPC2025_Guangzhouv2.pdf

17:15 Measurement of the accuracy and mixing-induced CP-violating parameters of $B_s^0 \to \phi\gamma$ at CEPC

The $b \to s\gamma$ is a critical FCNC process that could be used to probe CP violation (CPV) and New Physics (NP), especially in the context of future Z factory. The Circular Electron-Positron Collider (CEPC) offers inherent advantages for studying flavor physics, as it offers high statistic, clean collision environment, and superior detector performance. We quantify the anticipated precision of $B_s^0 \to \phi\gamma$ measurement at the CEPC Z pole modes, showing its signal strength could be determined to a relative accuracy of 0.16%, enhanced by roughly two orders of magnitudes compared to existing measurements. Additionally, we conduct a time dependent analysis of the $B_s^0 \to \phi\gamma$ decay, accounting for $B_s^0/\bar{B}_s^0$ mixing oscillations, and extract the mixing-induced and CP-violating parameters ${\mathcal{A}_{\phi\gamma}^\Delta}$, ${C_{\phi\gamma}}$ and ${S_{\phi\gamma}}$. The result are

$$ \begin{align*} {\mathcal{A}_{\phi\gamma}^\Delta} &= -0.67 \pm 0.0283(\text{stat}) \pm 0.0408(\text{syst}), \\ {C_{\phi\gamma}} &= 0.11 \pm 0.097(\text{stat}) \pm 0.0092(\text{syst}), \\ {S_{\phi\gamma}} &= 0.34 \pm 0.095(\text{stat}) \pm 0.0384(\text{syst}). \end{align*} $$

We also conduct a relative detector optimization study by establishing the correlation between the anticipated precision and the intrinsic resolution of the ECAL, as well as the performance of the PID system.

Speaker: Hengyu Wang (Institute of High Energy Physics)

Analysis of Bs2phigamma at CEPC.pdf

17:40 Flavor physics at high-energy muon colliders (online)

Speaker: Alfredo Glioti (EPFL)

Glioti.pdf

16:00 → 18:00 Software: 1

Zoom Link, ID:91076566347, Code:228773

Convener: Weidong Li (IHEP)

16:00 Gaussino Simulation Framework

Speaker: Gloria Corti (CERN)

Gsiso-GCorti-20251107.pdf

16:24 DIRAC and DIRACX

Speaker: Andrei Tsaregorodtsev (Centre de Physique des Particules de Marseille)

DIRAC_Status_CEPC_07112025.pdf

16:48 Panda System in the ATLAS Experiment

Speaker: Tatiana Korchuganova (University of Pittsburgh)

2025 CEPC PanDA in ATLAS .pdf

17:12 Quantum and Quantum-inspired Optimization for High Energy Colliders

Speaker: Hideki Okawa (中国科学院高能物理研究所)

okawa_CEPC2025_QOpt_20251107.pdf

17:36 Machine Learning in the ATLAS Experiment

Speaker: Bingxuan Liu (SunYat-sen University)

CEPC_Workshop_ML_Advances_In_ATLAS_BingxuanLiu.pdf

19:00 → 20:00 Poster: GroupA: Accelerator 1

19:00 [A01] Design and Calculation of the Vacuum System for High-Energy Linear Accelerator and Test Bench

Speaker: Pilong Tian (IHEP)

Poster-Pilong Tian.pdf

19:01 [A02] Application of Vibration Wire Measurement Technology in Pre-alignment Unit of HEPS Storage Ring

Speaker: Luping Yan (高能所)

Poster-Luping YAN-2025-10-28.pdf

Poster-Luping YAN-2025-10-28.pptx

19:02 [A03] SAD-Based Particle Tracking Simulation of Injection Efficiency and Beam Loss in SuperKEKB LER

Speaker: Mingyang Zhao

Poster Mingyang Zhao.pdf

19:03 [A04] Study on the Method for Successful Achievement of Vacuum Closed-Loop in the HEPS Storage Ring

Speaker: Tianfeng Liu

Poster-LiuTianfeng.pdf

19:04 [A05] Measurement of 3D distance from JUNO Detectors to Nuclear Power Reactors

Speaker: Xiaoyang Liu (高能所)

Measurement of 3D distance from JUNO Detector to Nuclear Power Reactors.pdf

Measurement of 3D distance from JUNO Detector to Nuclear Power Reactors.pptx

19:05 [A06] Analysis of absolute position alignment and absolute position deviation of the high energy photon source storage ring tunnel

Speaker: Haoyue Yan (中国科学院高能物理研究所)

HEPS absolute position alignment(Poster)-Yanhaoyue-03-2025-10-28.pdf

HEPS absolute position alignment(Poster)-Yanhaoyue-03-2025-10-28.pptx

19:06 [A07] Development of a hybrid superconducting dipole magnet with the magnetic field beyond 14 T

Speaker: Chengtao Wang (高能所)

CEPC--A07- Chengtao Wang.pdf

19:07 [A08] Closed-loop ReBCO Coil Under Varying Magentic Field: A Study of its Current Distribution and Dynamic Losses

Speaker: Hang Xu (IHEP)

poster-Hang Xu_1.pdf

19:08 [A09] Development of a CLIQ-Varistor Quench Protection Scheme for the LPF3-U Superconducting Dipole Magnet

Speaker: Yunqing Wang (中国科学院高能物理研究所)

Junqing Wang-CEPC2025-ReEdit1.pdf

19:09 [A10] Simulation and Experimental Validation of Inductive Excitation in HTS Flywheel Energy Storage System

Speaker: Rui Ma (中国科学院高能物理研究所)

CEPC海报-马瑞A-10(1).pptx

19:10 [A11] Electromagnetic Properties of Iron-Based Superconducting Uninsulated Double Pancake Coils and Their Comparison with REBCO Coils

Speaker: Fan Ren

Poster-任帆 .pdf

19:11 [A13] A low-level radio frequency (LLRF) control system for multiple superconducting cavities based on MicroTCA.4

Speaker: Wenbin Gao (IHEP, UCAS)

A Low-Level Radio Frequency (LLRF) Control System for Multiple Superconducting Cavities Based on MicroTCA.4.pdf

A Low-Level Radio Frequency (LLRF) Control System for Multiple Superconducting Cavities Based on MicroTCA.4.pptx

19:12 [A14] CEPC superconducting quadrupole magnets in interaction region

Speaker: Jieru Geng (IHEP)

A14_JieruGeng.pdf

19:13 [A15] Development of high power energy recovery absorbing load for large scale accelerators

Speaker: Yang Zhao (中国科学院高能物理研究所)

2025cepc-yangzhao（A15).pptx

19:00 → 20:00 Poster: GroupB: Accelerator II

19:00 [B01] Development of high voltage pulsed modulator for the CEPC C band 80MW Klystron

Speaker: Fei Li (IHEP)

CEPC_Poster2025_LiFei.pptx

19:01 [B02] Design of L-Band 10MW High Efficiency Multibeam Klystron

Speaker: Noman Habib (高能所)

CEPC 2025 poster latest.pdf

19:02 [B03] Development of a P-Band Energy-Recovering Klystron for CEPC

Speaker: Yu Liu (Institute for High Energy Physics)

CEPC_Poster2025_LiuYu .pdf

CEPC_Poster2025_LiuYu .pptx

19:03 [B04] Research on an S-Band 50 MW High-Efficiency Permanent Magnet Klystron

Speaker: Han Xiao (高能所)

2025CEPCWS_XiaoHan.pptx

19:04 [B05] Heat Load Investigation of Collector for High-Average Power Beam Dump of 80 MW Klystron for CEPC LINAC

Speaker: Munawar Munawar Iqbal (Centre for High Energy Physics)

Poster CEPC 2025 Dr.Munawar.pdf

19:05 [B06] Development of S-band high efficiency klystron

Speaker: Yiao Wang (Institute of High Energy Physics, Chinese Academy of Sciences)

CEPC2025_wangya.pdf

19:06 [B07] Development of 1.2 Mega-Watt P-band Travelling Wave Resonant Ring

Speaker: Fanyu Wang (高能物理研究所)

Development of 1.2 Mega-Watt P-band Travelling Wave Resonant Ring_Wang Fanyu.pptx.pdf

19:07 [B08] Electromagnetic and stability design of CEPC detector Superconducting magnet

Speaker: Menglin Wang

CEPC_poster_2025_wangmenglin.pdf

19:08 [B09] High Reliability Design for High Power RF Source Systems in Large Particle Accelerators

Speaker: Jindong Liu (高能所)

Reliability Design for High Power RF Source Systems in Large Particle Accelerators.pdf

Reliability Design for High Power RF Source Systems in Large Particle Accelerators.pptx

19:09 [B10] Optimization of Cavity Shape for C-Band Accelerating Structure

Speaker: Ghazal Rao (Institute of High Energy Physics)

poster_GHAZAL RAO IHEP stu.pdf

poster_GHAZAL RAO IHEP stu.ppt

19:10 [B11] RF design of a C-band spherical cavity pulse compressor

Speaker: Hengjun Cao (中国科学院高能物理研究所)

poster.pptx

19:11 [B12] Research on Scalable NEG Coating Techniques for CEPC Copper Vacuum Chambers : From Lab-Scale to Mass Production

Speaker: Fei Sun (高能所)

Research on Scalable NEG Coating Techniques for CEPC Copper Vacuum Chambers.pdf

19:12 [B13] Research on Methods for Improving the Plane Absolute Accuracy of the Control Network for the Circular Particle Accelerator

Speaker: Na Ma (高能所)

B13_NaMa.pdf

19:13 [B14] NEG coating and thermal coating spray of vacuum chamber

Speaker: Yongsheng Ma (高能所)

NEG coating and thermal coating spraying of vacuum chamber.pptx

19:14 [B15] Alternative Solution of RF Region Beam Separating System in CEPC

Speaker: Guanjian Wu (IHEP)

2025CEPC_Poster_Guanjian Wu.pdf

19:00 → 20:00 Poster: GroupC: Detector I

19:00 [C01] A 55 nm HV-CMOS Pixel Sensor Design for High-Energy Particle Tracking with High Hit Rate and Precise Time Resolution

Speaker: Leyi Li (中国科学院高能物理研究所（IHEP）)

CEPC_2025_poster_lileyi_revised.pdf

19:02 [C03] Irradiation study of COFFEE2 chips

Speaker: Tianyu Shi (高能所)

cepcws_coffee2_poster_v1.pdf

19:03 [C04] HVCMOS Pixel Sensor in 55nm Process: Readout Architecture Simulation, Hit Loss Analysis, and Data Transmission Optimization

Speaker: Xiaoxu Zhang (南京大学)

poster.pdf

19:04 [C05] A low-power 55 nm HV-CMOS pixel sensor readout architecture for the CEPC Inner Tracker

Speaker: Bingchen Yan (高能所)

ybc_CEPCposter.pdf

19:05 [C02] Current testing results of sensing diode, PLL, NMOS comparator and readout circuit of COFFEE3 pixel MAPS prototype for CEPC

Speaker: Boxin Wang (Institute of High Energy Physics, CAS)

boxin_cepc_poster_v1.pdf

19:05 [C06] Current testing results of the in-pixel CSA, discriminator, TDC, and readout circuit of COFFEE3 pixel MAPS prototype for CEPC

Speaker: Yuman Cai (IHEP)

CEPC2025_Poster_Yuman_CAi.pdf

19:06 [C07] TCAD simulation study of Novel AC-LGAD design with isolation Structures for sensor performance optimization

Speaker: Xu Huang (南昌大学)

Capacitance Optimization of AC-LGAD.pdf

19:07 [C08] KNN-Based Position Reconstruction Algorithm for AC-Coupled Low Gain Avalanche Detector

Speaker: Xiaoxu Zhang (南京大学)

poster_LGAD.pdf

19:08 [C09] Prototype assembly and tests for CEPC vertex detector

Speaker: Liangchenglong Jin

Prototype assembly and tests of CEPC vertex detector.pdf

19:09 [C10] Background Analysis and Digitization of CEPC Vertex Detector

Speaker: Hancen Lu (IHEP)

BKGAlyzDigitalCEPCWS.pdf

19:10 [C11] The Impact of Beam-Induced Backgrounds on the CEPC Vertex Detector Performance

Speaker: Zizi Kang (南开大学)

The Impact of BIBs on the CEPC VXD performance.pdf

19:11 [C12] Design Proposal for the CEPC Vertex Detector

Speaker: Tianyuan Zhang

CEPC2025posterF.pdf

19:00 → 20:00 Poster: GroupD: Detector II

19:00 [D01] Radiation hardness of 4H-SiC detectors for the CEPC Fast Luminosity Monitor Detector

Speakers: Jiaqi Zhou (Jilin University) , 嘉奇 周 (吉林大学)

poster.pdf

19:01 [D02] Research on the Electromagnetic Characteristics of No-Insulation Coils Wound with Aluminum-stabilized Stacked Tape Cable

Speaker: Qingyuan Li (中国科学院高能物理研究所)

CEPC—李青远.pdf

19:02 [D03] Design of Beam Monitoring Online System

Speaker: Sen Zhao

cepc_bmos.pdf

19:03 [D04] Bhabha event acceptance of the LumiCal at CEPC

Speaker: Jiading Gong (Jilin University)

Bhabha_Event.pdf

19:04 [D05] Simulation Studies of the Effect of SiPM Dark Noise on the Performance of a Highly Granular Crystal ECA

Speaker: Jack ROLPH JACK CHRISTOPHER HUTCHIN (IHEP)

Poster.pdf

19:05 [D06] Beam test results and uniformity studies of high-density glass scintillator tiles

Speaker: Dejing Du (IHEP)

2025_11_poster_D06.pdf

19:06 [D07] Beamtest data analysis and simulation validation for the CEPC AHCAL prototype

Speaker: Dejing Du (IHEP)

2025_11_poster_D07.pdf

19:07 [D08] Design of the CEPC Gaseous Tracking Detector and Research on Particle Identification

Speaker: Jianbo Zheng (高能所)

Design_of_the_CEPC_Gaseous_Tracking_Detector_and_Research_on_Particle_Identification.pdf

19:08 [D09] The Construction of a Drift Chamber Prototype

Speaker: Jing Dong (高能所)

186_JingDong3Nov.pdf

19:09 [D10] Fast Simulation of the CEPC Long-Bar Crystal Electromagnetic Calorimeter

Speaker: Zhihao Li (IHEP)

poster.pdf

19:10 [D11] A Concurrent and Distributed Analysis Framework for Large-Scale High-Energy Physics Experiments

Speaker: Shuzhu Jin (高能所)

poster.pptx

Saturday, 8 November

09:00 → 10:30 Accelerator: 7

Zoom Link, ID:93618001420, Code:427946

Convener: wenhui huang (Tsinghua University)

09:00 PAL accelerator activities

Speaker: Garam Hahn (Pohang Accelerator Laboratory, POSTECH)

20251108-HTS_WLS_StatusReport-public-v7.pdf

09:18 CEPC machine protection with collimators and transport line systems

Speaker: Xiaohao Cui (Accelerator Center)

CEPC machine protection-V2 .pptx

09:36 CEPC dumps and the dump experimental hall

Speaker: Zhongjian Ma (IHEP)

CEPC dumps and the dump experimental hall-mazhj-2025.pptx

09:54 CEPC Mechanical system EDR plan and status

Speaker: Haijing Wang (高能所)

CEPC Mechanical system EDR plan and status_guangzhou 2511.pptx

10:12 CEPC alignment and installation EDR plan and status

Speaker: Xiaolong Wang (高能所)

CEPC alignment and installation EDR plan and status - 副本.pptx

09:00 → 10:50 BSM: 1

Zoom Link, ID:96812316331, Code:367916:

Convener: Tao Liu (The Hong Kong University of Science and Technology)

09:00 Status of the 152 GeV Candidate at the LHC

The discovery of a Higgs boson at the LHC consistent with the predictions of the Standard Model (SM) marked a major milestone in particle physics. In this context, the search for new Higgs-like bosons remains at the forefront of efforts to explore physics beyond the SM.

Based on several features observed in the data collected during Run 1 of the LHC, a simplified model was proposed in which a heavy scalar, $H$, decays into a combination of the SM Higgs boson ($h$) and a new Higgs-like scalar, $S$. One implication of this model is the appearance of excesses in lepton production when the decay $S \rightarrow WW$ dominates. These excesses, referred to as the multi-lepton anomalies at the LHC, were subsequently identified. They include events with two or more leptons, missing transverse energy, and ($b$)-jets in the final state. Based on the invariant mass of lepton pairs, the mass of the new scalar is predicted to be $m_S = 150 \pm 5\,\mathrm{GeV}$.

The analysis of $\gamma\gamma$, $Z\gamma$, and $WW$ sideband spectra in Run 2 data confirms the presence of a resonance at $m_S = 152 \pm 1\,\mathrm{GeV}$, with a global significance of $5.3\sigma$. This represents the strongest excess observed at the LHC to date that is consistent with a narrow resonance beyond the SM. These findings strongly motivate further investigation at future high-precision facilities such as the CEPC.

Speaker: Bruce Mellado (University of the Witwatersrand)

CEPC2025_152_081125.pdf

09:20 Indications for a 152 GeV Higgs boson

The statistical significance of the multilepton anomaly - the discrepancies in the channels with multiple leptons, missing energy, and (b-) jets in the final states with the SM prediction -indicates the production of a scalar with mass between 145 and 155 GeV that is beyond the standard model. The associated production of a narrow scalar resonance of mass around 150 GeV, with a significance of $5.3\sigma$ has been reported with the analysis of $\gamma\gamma$, $Z\gamma$, and $WW$ sideband spectra in Run 2 data. The requirement of the new scalar to decay dominantly to $WW$ final state by the multi-lepton anomalies and the absence of any excess in $ZZ$ final state significantly indicates the new scalar to be part of $Y = 0$ scalar-triplet. The model contains a $CP$-even neutral Higgs ($\Delta^0$), and two charged Higgs bosons ($\Delta^\pm$), which are quasi-degenerate in mass. Identifying the charged scalar at the LHC is difficult due to large SM backgrounds, production rates suppressed by small mixing angles
($\alpha$, $\beta$), and low detection efficiency for its moderately energetic leptons. This motivates dedicated searches at future $e^+e^-$-colliders, where the cleaner environment and well-defined initial state make $e^+ e^- \to \gamma^∗/Z \to \Delta^\pm \Delta^\mp$ the primary production channel. In this article, we focus on the possibility of finding the aforementioned predicted around 150 GeV BSM charged scalar at the future proposed $e^+ e^-$− collider. We emphasize on the pair production of the charged scalars, $e^+ e^- \to \Delta^\pm \Delta^\mp$ and scrutinize various signal regions depending on the decay products of $\Delta^\pm$.

Speaker: Andreas Crivellin (U)

09:50 Computational tools for the Future Colliders

In this talk, I will present new computational methods for Monte Carlo simulations based on machine learning techniques, as well as data analysis approaches utilizing quantum computing. These developments are aimed at supporting future high-energy collider programs, including the planned SPPC, as an extension of the CEPC framework.

Speaker: Myeonghun Park

PARC.pdf

10:10 A New Probe for Long-Lived Particles at Higgs Factories: Displaced Photons in the Hadronic Calorimeter

Speaker: Jinhan Liang (Nanjing University)

CEPC-LLP-251111-CEPC2025-Guangzhou-Jinhan-Liang.pdf

09:00 → 10:30 Calorimetry: 3

Zoom Link, ID:97990003364, Code:309122

Convener: Haijun Yang (Shanghai Jiao Tong University)

09:00 Dual-readout fiber-based calorimeter: prototype developments and R&D program

Speakers: Roberto Ferrari (INFN-PV) , Roberto Ferrari (INFN)

cepc.guangzhou.roberto.2025.11.08.pdf

09:30 Test Beam Performance of a Dual-Readout Fiber Calorimeter Prototype

Speaker: Seoyun Jang (Yonsei University (KR))

SYJ_CEPC_DRC_1108.pdf

10:00 Testbeam studies of scintillator-based ECAL and HCAL prototypes

Speaker: Hongbin Diao (University of Scinence and Technology of China)

Testbeam studies of scintillator-based ECAL and HCAL prototypes.pdf

09:00 → 10:30 MDI: Mechanical + Integration

Mechanical and Integration Zoom Link, ID:91076566347, Code:228773

MDI + Accelerator Zoom Link, ID:93618001420, Code:427946

Convener: Xiaoyan Ma (高能所)

09:00 CEPC Interaction Region engineering design status

Speaker: Haijing Wang (IHEP)

CEPC Interaction Region engineering design status_guangzhou2511.pptx

09:18 Overview of BESIII installation

Speaker: Xiaoping Jin (IHEP)

Overview of BESIII installation 20251106.pptx

09:36 Challenge of detector installation and Integration of CEPC

Speaker: Xiaohui Qian (IHEP)

CEPC challenge .pdf

09:54 Yoke progress of CEPC detector

Speaker: Shang Xia (中国科学院高能物理研究所（IHEP）)

Yoke Progress of CEPC detector-20251108.pdf

10:12 Mechanical design of CEPC HCAL

Speaker: Yatian Pei (IHEP)

2025HCAL-Mechanics-guangzhou.pdf

2025HCAL-Mechanics-guangzhou.pptx

10:30 → 11:00 Coffee break

10:50 → 12:50 BSM: 2

Zoom Link, ID:96812316331, Code:367916:

Convener: Minho Son

10:50 CEPC BSM Overview

Speaker: Yongchao Zhang (Southeast University)

BSM_CEPC_Guangzhou.pptx

11:10 Unraveling dark Higgs mechanism via dark photon production at ep collider

Speaker: Mengchao Zhang (itp)

11:30 Light Axion-Like Particles at Future Lepton Colliders

Axion-like particles (ALPs) are well-motivated extensions of the Standard Model (SM) that appear in many new physics scenarios, with masses spanning a broad range. In this work, we systematically study the production and detection prospects of light ALPs at future lepton colliders, including electron-positron and multi-TeV muon colliders. At lepton colliders, light ALPs can be produced in association with a photon or a Z boson. For very light ALPs, the ALPs are typically long-lived and escape detection, leading to a mono-V (V=photon,Z) signature. In the long-lived limit, we find that the mono-photon channel at the Tera-Z stage of future electron-positron colliders provides the strongest constraints on ALP couplings to SM gauge bosons, thanks to the high luminosity, low background, and resonant enhancement from on-shell Z bosons. At higher energies, the mono-photon cross section becomes nearly energy-independent, and the sensitivity is governed by luminosity and background. At multi-TeV muon colliders, the mono-Z channel can yield complementary constraints. For heavier ALPs that decay promptly, mono-V signatures are no longer valid. In this case, ALPs can be probed via non-resonant vector boson scattering (VBS) processes, where the ALP is exchanged off-shell, leading to kinematic deviations from SM expectations. We analyze constraints from both light-by-light scattering and electroweak VBS, the latter only accessible at TeV-scale colliders. While generally weaker, these constraints are robust and model-independent. Our combined analysis shows that mono-V and non-resonant VBS channels provide powerful and complementary probes of ALP-gauge boson interactions.

Speaker: Shoushan Bao (Shandong University)

ALPs at Future Lepton Colliders.pdf

11:50 Probing Reheating through UV Freeze-in Dark Matter at Lepton Colliders

Dark matter (DM) genesis via Ultraviolet (UV) freeze-in embeds the seed of
reheating temperature and dynamics in its relic density. Thus, the discovery of such a DM candidate can possibly open the window for post-inflationary dynamics. However, there are several challenges in this exercise, as freezing-in DM possesses feeble interaction with the visible sector and therefore very low production cross-section at the collider. We show that mono-photon (and dilepton) signal at the electron-positron collider, arising from DM effective operators connected to the SM field strength tensors, can still warrant a signal discovery. We study both the scalar
and fermionic DM production during reheating via UV freeze-in, when the inflaton oscillates at the bottom of a general monomial potential. Interestingly, we see that right DM abundance can be achieved only in the case of bosonic reheating scenario, satisfying bounds from big bang nucleosynthesis (BBN). This provides a unique correlation between the collider signal and the post-inflationary dynamics of the Universe within single-field inflationary models

Speaker: Sahabub Jahedi (South China Normal University)

Sahabub_CEPC25.pdf

12:10 Effective field theory for type II seesaw model: symmetric phase v.s. broken phase

The two popular frameworks for the effective field theory (EFT) describing physics beyond the standard model are the Standard Model EFT (SMEFT) and the Higgs EFT (HEFT). In this work, we present another framework, called broken phase effective field theory (bEFT), in which we deal directly with mass eigenstate fields after spontaneous symmetry breaking without employing nonlinear realization. We take the type-II seesaw model as an example to demonstrate our approach. We evaluate the Higgs pair production process through the vector boson fusion in the LHC and the Higgsstrahlung process in the linear collider. We find that our bEFT reproduces the type-II seesaw model more accurately than the SMEFT in the large parameter regions.

Speaker: Yoshiki Uchida (South China Normal University)

20251108_CEPC2025.pdf

11:00 → 12:30 Accelerator: 8

Zoom Link, ID:93618001420, Code:427946

Convener: Garam Hahn (Pohang Accelerator Laboratory, POSTECH)

11:00 Accelerator activities in Tsinghua University

Speaker: Wenhui Huang (Tsinghua University)

2025_VIGAS_Tsinghua_CEPC25.pdf

11:18 CEPC RF power sources and power distribution EDR plan and status

Speaker: Zusheng Zhou (IHEP)

ZHOU Zusheng-RF Power sources.pptx

11:36 CEPC powers sources in EDR

Speaker: Bin Chen (高能所)

20251108 CEPC Magnet Power Supply System Status in EDR.pptx

11:54 CEPC injection and extraction hardware

Speaker: Jinhui Chen (Institute of High Energy Physics)

CEPC injection and extraction hardware-CEPCWorkshop2025-20251108-final-upload.pdf

CEPC injection and extraction hardware-CEPCWorkshop2025-20251108-final-upload.pptx

11:00 → 12:30 Calorimetry: 4

Zoom Link, ID:97990003364, Code:309122

Convener: Dr Yong Liu (Institute of High Energy Physics)

11:00 CMS High-Granularity Calorimeter (HGCAL) Upgrade

Speaker: Zirui Wang (复旦大学 Fudan University)

wangzr20251108_CEPCWorkshop.pdf

11:30 LHCb Calorimeters Upgrade

Speaker: Hengne Li (South China Normal University)

20251108CEPCWS25_LHCbPicoCal_v2.pdf

12:00 Fully digital 110 nm CMOS SiPM for fast amplitude and timing measurements

Speaker: Prof. Lodovico Ratti (INFN Pavia, University Pavia)

ratti_cepc25.pdf

11:00 → 12:30 Electronics: Electronics, Overall and FEE

Zoom Link, ID:91076566347, Code:228773

Convener: Prof. Weihao Wu

11:00 The overall readout out electronics for the reference detector at CEPC

Speaker: Prof. Zheng Wang

Zheng_CEPC electronics.pdf

Zheng_CEPC electronics.pptx

11:30 Sensor and electronics design for the Vertex Detector

Speaker: Dr Ying Zhang

Electronics_VTX_20251108_f.pdf

11:50 The readout for the silicon Tracker

Speaker: Dr Xiongbo Yan

The readout for the silicon Tracker.pdf

12:10 Development of Interposer based pixel TPC Readout

The Time Projection Chamber (TPC) can provide accurate measurement of the three-dimensional trajectory of charged particles and distinguish between low object mass particles and dE/dx, so it is widely used in high-energy particle physics experiments. For example, in the Ring Positron Collider (CEPC) experiment, TPC became the detector of choice for the main track detector. In order to achieve a 100-microns track resolution, TPC typically uses smaller readout pads, resulting in a dramatic increase in readout electronics density and channel count.
To meet the stringent demands on high rate and PID, pixel TPC is essential for CEPC tracking system. An interposer-based pixel readout for CEPC TPC has been proposed and a demonstrator of 500um x 500um pixels was developed, together with a multi-channel readout ASIC – TEPIX. TEPIX consists of 128 channels and each channel contains a CSA, a CDS, a 14-bit Wilkinson ADC and a 14-bit TOA. TEPIX works at a frame sampling mode and can provide information of charged particles, including time and energy. The power consumption of TEPIX is less than 0.5 mW/ch. The tested ENC is about 300e @0pF. This talk carries out the development and test results of interposer-based pixel readout to meet the high-density readout requirements of TPC detectors.

Speaker: Zhi Deng (清华大学)

12:30 → 14:00 Lunch break

14:00 → 15:30 BSM: 3

Zoom Link, ID:96812316331, Code:367916:

Convener: Francisco Arco (DESY)

14:00 The Higgs Factory-Gravitational Wave Interface

Speakers: Michael Ramsey-Musolf (SJTU/TDLI) , Michael Ramsey-Musolf (U)

MJRM CEPC 25 Higgs Factory GW.pdf

14:30 Long-lived dark sector at lepton colliders

Speakers: Lingfeng Li (Brown University) , Lingfeng Li (HKUST)

Dark_Sector_CEPCWS.pdf

14:50 Lam-Tung relation breaking effects and weak dipole moments at colliders

Speaker: Bin Yan (IHEP)

Lam_Tung_BY.pdf

15:10 Z/W resonance schemes

Speaker: Shaofeng Ge

251108_CEPC.pdf

14:00 → 15:30 Electronics: Electronics, FEE and ASICs

Zoom Link, ID:91076566347, Code:228773

Convener: Weihao Wu (Shanghai Jiao Tong University)

14:00 The readout for the ECAL/HCAL

Speaker: Jinfan Chang (高能所)

14:15 The readout for the Muon

Speaker: Jie Zhang (Institute of High Energy Physics)

muon electronics2025-11.pdf

14:30 SIPAC A SiPM readout ASIC for the CEPC Detector

The Circular Electron Positron Collider (CEPC) is proposed for Higgs boson research, and will includes several detectors, such as the Electromagnetic Calorimeter (ECAL), Hadronic Calorimeter (HCAL), and Muon detector. Silicon photomultiplier (SiPM) is widely used in these detectors for light conversion. This paper presents a prototype design of SIPAC (SiPM readout ASIC for calorimeter).
Table 1 outlines the readout requirements of the ECAL and HCAL. Given the limitations of existing commercial chips and the CEPC detector’s requirement for a large-scale deployment of SiPM and their associated readout circuits, a dedicated SIPAC readout chip has been developed. With a maximum input charge of 3.84 nC, employing a CSA as the front-end amplifier would necessitate an impractically large input capacitor. To realize SiPM voltage adjustment, AC coupling is implemented between the preamplifier and the SiPM. Furthermore, given the slow response of the SiPM signal after passing through the crystal, SIPAC utilizes voltage amplifier as the front-end solution. Given the critical impact of the noise on time and energy resolution, the design of the shaper is critical. The energy path employs a slow shaper with two stages of low-pass filters, achieving an SNR of 8, while the timing path uses a fast shaper with a Bandpass filter, achieving an SNR of 12. Signals after shaping are sampled or compared, then quantized by the ADC or TDC and read out by the digital module. The four channels’ switched capacitor sampled signals are processed by a shared ADC and serializer for conversion and output, with each channel featuring a dedicated TDC. Figure 1 shows the overall architecture.
To address the gain variations between different SiPMs, an on-chip DAC is integrated into each channel for precise gain calibration of each SiPM. AC coupling is implemented for signal transmission, effectively isolating the adjustment effects of the DAC from the readout circuit. The signal after shaper is sampled by a switched-capacitor circuit and digitized by the SAR ADC for energy measurement. As shown in Figure 2, the post-simulation results indicate that within the input dynamic range of 1.28 pC to 3.84 nC, the nonlinearity errors are 0.4% for the high-gain path and 0.3% for the low-gain path. Furthermore, the SAR ADC achieves an ENOB of 10 bits.
For the time measurement path, the TDC employs a hybrid measurement structure combining coarse counting and fine counting. The coarse counting is derived from a counter, while the fine counting is determined by a delay line. The TDC is designed to measure the time of arrival (TOA). The digital codes generated by the TDC and ADC are encoded and serialized by the digital module for data transmission.
In summary, SIPAC, a dedicated SiPM readout ASIC for the CEPC detector, features a wide dynamic range (1.28 pC to 3.84 nC), supports a 500 kHz event rate, and achieves a 200 ps time resolution at 1.28 pC. The integrated TDC delivers 100 ps resolution with INL and DNL below 1 LSB, while the ADC achieves a 10-bit ENOB.
Currently, the chip is undergoing functional testing. The front-end circuit and TDC are working normally, and the ADC is under testing. It is expected that the accuracy of the TDC will reach 100ps, and the dynamic range of the front-end meets the design requirements. Detailed performance tests will be conducted after the functional tests are completed.

Speakers: Huaishen Li (IHEP) , Yunqi Deng (高能所)

SIPAC A SiPM readout ASIC for the CEPC Detector.pdf

14:50 A Low-Power Timing Chip Prototype for Strip LGAD Readout

AC-coupled Low Gain Avalanche Detector (AC-LGAD) based microstrip, achieving 30 ps timing resolution with a 100 µm pitch, is proposed for the OTK in CEPC. The inherent capacitance of AC-LGAD presents significant challenges for power optimization. To match the strip pitch, a LGAD Timing Readout Integrated Chip (LATRIC) integrating 128 channels with a height of less than 100 µm per channel is proposed. A single-channel prototype, LATRIC0, is fabricated in a 55 nm process for functional verification and integrates a front-end amplifier, a time-to-digital converter (TDC) core, and two serializers for outputting encoded and raw data. For analysis and debug, both a 128-bit low-speed serializer and a 40-bit high-speed serializer are included to output raw and encoded data, respectively.
The TDC core is implemented with a compact layout height under 65 µm, including a timing controller, an event-driven ring oscillator with quantization logic, and an encoder. Upon an event trigger, the timing controller produces an enable signal to start the ring oscillator, along with separate latch signals for measuring the time of arrival (TOA) and time over threshold (TOT). A calibration (CAL) mechanism is incorporated via an additional clock cycle in the latch signal. The ring oscillator, which consists of 15 delay cells, supports simultaneous TOA, TOT, and CAL measurements.
Test results show that the TDC achieves an average bin-size of about 30 ps for both TOT and TOA. Both the tested integral and differential non-linearity are below 1 LSB.
Measurement results indicate that the average power consumption for the TDC measurement is below 0.12 mW at a 500 kHz event rate. The power consumption of the pre-amplifier and TDC block combined is less than 5.88 mW.
More detailed testing is in progress.

Speakers: Chuanye Wang, Xiongbo 严雄波 YAN Xiongbo (高能所)

CEPC2025report.pdf

15:10 Design and Verification of the Digital Subsystem for the FEDI

Speaker: Xiaomin Wei (Northwestern Polytechnical University)

CEPC FEDI ASIC v3.pdf

CEPC FEDI ASIC v3.pptx

14:00 → 15:40 Gaseous Detector: 1

Zoom Link, ID:97990003364, Code:309122

Convener: Nicola De Filippis (Politecnico and INFN Bari)

14:00 TPC techonolgy in CEPC TDR

Speaker: Huirong Qi (Institute of High Energy Physics, CAS)

CEPC_TPC_Guangzhou_Huirong_20251108.pdf

14:20 BG estimaiton and simuation for TPC

Speaker: Xin She (IHEP,CAS)

CEPCWorkshop_BGonTPC_shexin_v00.pdf

14:40 Pixel-type reaoud chips R&D

Speaker: Yue Chang (Central China Normal University (CCNU))

CEPC2025_Changyue.pdf

15:00 Muon gas detectors

Speaker: Shikma Bressler (W)

2025_11_CEPC_WS_Bressler.pdf

15:20 Application of MRPC in Muongraphy

Speakers: Dr Daming Liu (Tsinghu University) , Wang Yi (Tsinghua University)

刘大铭Application of MRPC in Muography.pdf

14:00 → 15:30 MDI: +Accelerator 1

Mechanical and Integration Zoom Link, ID:91076566347, Code:228773

MDI + Accelerator Zoom Link, ID:93618001420, Code:427946

Conveners: Haoyu SHI (IHEP) , Suen Hou (IPAS)

14:00 CEPC MDI EDR Status and Plan (remote)

Speaker: Sha Bai (高能所)

CEPC MDI EDR plan and status.pptx

14:18 Luminometer at CEPC

Speaker: Lei Zhang (Nanjing University)

2025Oct_Guangzhou_CEPCLumi-v1.pdf

14:36 CEPC Detector Solenoid Magnet Design

Speaker: Feipeng Ning (IHEP)

CEPC detector magnet design-GuangZhou.pptx

14:54 Background Experiences at BEPCII-U (remote)

Speaker: Bin Wang (IHEP)

20251108_CEPC_workshop_BinWang_v2.pptx

15:12 CEPC MDI vacuum system

Speaker: Lei Zhang (IHEP)

CEPC MDI Vacuum-2025.11.08.pptx

15:30 → 16:00 Coffee break

16:00 → 18:00 EW & tt: 1

Conveners: Alessandro Vicini (University of Milano) , Janusz Gluza (U. of Silesia) , Jiayin Gu (Fudan University) , Xiaohu SUN (Peking University)

16:00 New developments in the ReneSANCe event generator

We give a report on new developments in the ReneSANCe Monte Carlo event generator and its application to the processes used for luminosity monitoring such as small/large angle Bhabha scattering e+e- -> e+e-, e+e- -> gamma gamma and e+e- -> mu+mu-. One-loop EW and higher order corrections, beam energy spread, polarization, and a number of background processes are taken into account.

Speaker: Dr Renat Sadykov (Joint Institute for Nuclear Research)

sadykov_cepc_2025.pdf

16:24 Toponium results from ATLAS and CMS

Speaker: Haifeng Li (Shandong University)

20251108-Toponium-CEPC.pdf

16:48 Higher-order ISR corrections to electron-positron annihilation processes

Radiative corrections due to initial state radiation in electron-positron annihilation are calculated within the QED structure function approach. Results are shown in the next-to-leading logarithmic approximation up to O(alpha^4L^3) order, where L=ln(s/m^2_e) is the large logarithm. Dependence on factorization scale and scheme choices is analyzed. The results are relevant for future high-precision experiments at e+e− colliders.

Speaker: Andrej Arbuzov (Joint Institute for Nuclear Research)

arbuzov_CEPC_2025.pdf

17:12 ZH NNLO

Speaker: Qian Song (University of Pittsburgh)

CEPC2025.pdf

17:36 Recasting tt and ttZ measurements

Speaker: Andreas Crivellin (U)

16:00 → 18:05 Electronics: Electronics: ASICs, Detector Powering, BEE, and COTS

Zoom Link, ID:91076566347, Code:228773

Convener: Jingbo Ye

16:00 The development of FEDA

Speakers: Guoxiang Zhang, Le Xiao (ccnu)

The development of FEDA_FINAL.pdf

16:20 The Development of High-Speed TIA and VCSEL Driver ASICs for Optical Data Transmission in HEP

Speakers: Wei Dai, Di Guo (华中师范大学)

CEPC ATIA_ALDD(1).pdf

16:40 The development of the configuring circuits (I2C, SPI)

Speaker: Wei Zhang (武汉纺织大学)

16:55 The development of the FEE-Powering: DC-DC, LDO

Speaker: Jia Wang (西北工业大学)

CEPC_Workshop_Guangzhou2025.pdf

17:10 The development of the common BEE

Speaker: Jun Hu (IHEP, CAS)

BEEdesign.pdf

17:30 First RISC-V–Based System-on-Chip for CEPC Readout ASICs

High-Energy Physics (HEP) experiments increasingly rely on complex ASICs, driving a growing need for flexible, programmable architectures. We present a RISC-V–based System-on-Chip (SoC) that serves as a versatile control and configuration hub for CEPC ASICs. The SoC integrates tiny_riscv, a lightweight 32-bit processor with a 3-stage pipeline, capable of executing C programs to manage registers and implement communication protocols such as I²C and SPI via firmware. Its application will first be demonstrated in LATRIC, an ASIC for Low-Gain Avalanche Diode (LGAD) readout, with fabrication planned in a 55 nm CMOS process in October. This talk will present the SoC design, its implementation for CEPC ASICs, and prospects for future development and applications.

Speakers: Yuxin Cui (中国科学院高能物理研究所) , 娇龙 陈

riscv_en.pdf

17:50 FPGA-Based Front-End Electronics for AC-LGAD Detector

Speakers: Kun Hu, Liyan Jin, 梁志均 LIANG Zhijun

FPGA-based FEE for AC-LGAD - cepc.pdf

FPGA-based FEE for AC-LGAD - cepc.pptx

16:00 → 17:30 Gaseous Detector: 2

Zoom Link, ID:97990003364, Code:309122

Convener: Shikma Bressler (W)

16:00 Status and future of DRD1 international collaboration

Speakers: Dr Eraldo Oliveri (CERN) , Maxim Titov (CEA Saclay, Irfu)

Status_fulture_Eraldo_DRD1_CEPCWS_2025.pdf

16:30 Drift-field distortions in the ALICE TPC in LHC Run 3

Speaker: Dr Matthias Kleiner (CERN)

CEPC_2025_Matthias_Kleiner.pdf

16:55 A Pixel TPC as a central tracker in a CEPC experiment

Speaker: Peter Kluit (Nikhef)

TPC_PixelTracker_CEPC.pptx

16:00 → 18:00 MDI: +Accelerator 2

Mechanical and Integration Zoom Link, ID:91076566347, Code:228773

MDI + Accelerator Zoom Link, ID:93618001420, Code:427946

Conveners: Ivanka Bozovic (Vinca Institute of Nuclear Sciences) , Sha BAI (高能所)

16:00 Challenges of MDI for future Higgs factories (remote)

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

251108_MDI challenges_Mboscolo CEPC Workshop 2025.pdf

16:23 Measuring QED Radiative Bhabha to 10^-4 with the LumiCal

Speaker: Suen Hou (IPAS)

20251108-RadBhabha-v2a.pdf

16:43 Electromagnetic deflection in integrated luminosity measurement at the CEPC Z-pole (remote)

Speaker: Ivan Smiljanic (VINCA Institute of Nuclear Sciences)

CEPC_EMD_Ivan_WSNov25.pdf

17:03 State-of-the-art of radiation-hard sensors studies (remote)

Speaker: Konstantin Afanaciev (IPE NAS Belarus)

akg_cepc_radhard_2025.pdf

17:23 Simulation for the CEPC fast luminosity monitor detector based on 4H-SiC

Speaker: Yanpeng Li (吉林大学)

CEPCworkshop2025.pdf

CEPCworkshop2025.pptx

17:40 Luminosity monitoring at SuperKEKB - lessons learned (remote)

Speakers: Philip Bambade (IJCLab - CNRS - IN2P3) , Prof. Phillip Bambade (IJCLab)

Luminosity monitoring for IP beam tuning at SuperKEKB - Guangzhou.pptx

17:30 → 18:30 IB meeting

19:00 → 21:30 Banquet

Sunday, 9 November

09:00 → 10:30 Accelerator: 9

Zoom Link, ID:93618001420, Code:427946

Convener: Makoto Tobiyama (KEK Accelerator Laboratory)

09:00 Accelerator activities in Beijing University

Speaker: Qianyi Ma

09:18 CEPC control system

Speaker: Dapeng Jin (Institute of High Energy Physics, CAS, China)

Control System20251109.pptx

09:36 IHEP plasma accelerator test facility status

Speaker: Dazhang Li (IHEP)

09:54 Theoretical studies on high-energy plasma wakefield acceleration

Speaker: Ming Zeng (Tsinghua University)

09:00 → 10:30 EW & tt: 2

Conveners: Alessandro Vicini (University of Milano) , Janusz Gluza (U. of Silesia) , Jiayin Gu (Fudan University) , Xiaohu SUN (Peking University)

09:00 Top mass at CEPC

Speaker: Xiaohu Sun (Peking University)

mTop-CEPC-XiaohuSUN-CEPC2025NOV.pdf

09:22 Effective weak mixing angle at CEPC

Speakers: Zhenyu Zhao, 振宇 赵 (University of Science and Technology of China)

20251109-stw_measurement_on_the_CEPC.pdf

09:45 Two-Loop Electroweak Radiative Corrections to Low-Energy Electron-Electron Scattering

Parity-violating electron scattering is a powerful tool for precision tests of the Standard Model, enabling highly accurate measurements of the weak mixing angle. The upcoming MOLLER experiment at the Jefferson Lab will measure the electron's weak charge with 0.1% precision, providing sensitivity to new physics at the O(10) TeV scale. This talk will present recent theoretical work aimed at reducing the associated theoretical uncertainties to a level that matches or surpasses this experimental target.

Speaker: Yong Du (IMP CAS)

CEPC2025-YongDu.pdf

10:07 Quantum Entanglement at Higgs Factory

Speaker: 昊 ZHANG (Institute of High Energy Physics, Chinese Academy of Sciences)

haozhang.pdf

09:00 → 10:31 Gaseous Detector: 3

Zoom Link, ID:97990003364, Code:309122

Convener: Dr Huirong Qi (Institute of High Energy Physics, CAS)

09:00 DC in IDEA as a alternative concept

Speaker: Nicola De Filippis (Politecnico and INFN Bari)

DeFilippis_DCH_CEPC2025.pdf

09:25 Status of DC R&D

Speaker: Wenyu Pan (中国科学院高能物理研究所)

Study of Primary Ionization Counting Method in Drift Chamber.pdf

09:47 PID using gaseous detector

Speaker: Jinxian Zhang

PID performance of high-granularity readout TPC for future e+e− colliders.pdf

10:09 Micromegas detector R&D for the high energy experitments

Speaker: Xu Wang (USTC)

Micromegas_CEPC_workshop2025.pdf

09:00 → 10:30 TDAQ: 1

Zoom Link, ID:91076566347, Code:228773

Convener: Miroslav Saur (Lanzhou University)

09:00 Level-1 Trigger and Scouting with Phase-2 Upgraded CMS Detector on the HL-LHC

Speaker: Vladimir Rekovic (Vinca Institute, University of Belgrade (Serbia))

CMS_Trigger_VRekovic_CEPC_2025.pdf

09:30 L1 trigger design progress on CEPC ref-Detector TDR

CEPC ref-Detector TDR is finished and submmitted for publish.CEPC plans to run at a non-empty bunch crossing rate of 1.34–40 MHz.Background data throughput will be from 100 GB/s (Higgs mode) to 1 TB/s (Z-boson pole). Simulations show the trigger system can reduce rates to the range of few to tens of GB/s efficiently and event rate to 30 kHz (Higgs) and 120 kHz (low lumi-Z). The L1 trigger employs a three-stage hardware system: the first stage generates module-level triggers from backend electronics; subsequent stages integrate sub-detector triggers and execute global selection.The L1 signals are sent to Backend Electronic of each detector for data readout via the TCDS(Trigger and Clock Distribution System).This report will show more detials of L1 trigger system design and progress on the R&D.

Speaker: Jingzhou Zhao (高能所)

CEPC workshop 2025_guangzhou_L1T_v0.1.pdf

09:50 Trigger simulation progress

Speaker: Boping Chen

CEPCworkshop2025guangzhou.pdf

10:10 Real time and AI integrated data processing system

Speaker: Zhaozhi Liu (SDU)

CEPC2025d.pdf

10:30 → 11:00 Coffee break

11:00 → 12:30 Accelerator: 10

Zoom Link, ID:93618001420, Code:427946

Convener: Jie GAO (IHEP)

11:00 CEPC polarization study status

Speaker: Zhe Duan (高能所)

CEPC_polarization_status_v5.pptx

11:18 CEPC polarized electron source R&D

Speaker: Xiaoping LI (高能所)

CEPC polarized electron source R&D.pdf

11:36 The status of accelerator design program kit: APES

Speakers: Tianmu Xin, Yuan Zhang (IHEP, Beijing)

20251109-APES-ZhangYuan_TXIN.pptx

11:54 Recent progresses for laser plasma accelerators and their applications at Peking University

Speaker: Qianyi Ma (School of Physics, Peking University, Beijing 100871, China)

11:00 → 12:30 EW & tt: 2

Conveners: Alessandro Vicini (University of Milano) , Janusz Gluza (U. of Silesia) , Jiayin Gu (Fudan University) , Xiaohu SUN (Peking University)

11:00 Measurement of the Forward–Backward Asymmetry in 𝑒⁺𝑒⁻ → μ⁺μ⁻ at the CEPC 𝑍 Pole with the TDR Reference Detector

The Circular Electron–Positron Collider (CEPC) enables high-precision electroweak studies at the 𝑍 pole. We present a simulation-based study of the forward–backward charge asymmetry ($A^\mu_{FB}$) in $e^+e^-\to\mu^+\mu^-$ events using the TDR reference detector. After optimized event selection, the signal efficiency reaches about 90% with negligible background contamination. Signal and background samples are generated including $\gamma^*/Z$ interference and QED radiation, and the simulated asymmetry agrees with the LEP result. Systematic effects from muon identification, background, detector resolution, beam energy spread and beam energy calibration are evaluated. Assuming one month of low-luminosity $Z$-pole running in the first CEPC $ZH$ operation year, corresponding to $4\times10^{10}$ $Z$ bosons, the expected precision on $A^\mu_{FB}$ is $\pm3.1\times10^{-5}$ (stat.) and $\pm2.8\times10^{-5}$ (syst.), improving the LEP accuracy by two orders of magnitude.

Speaker: 家威 万 (Nanjing University)

ee to mumu AFB at CEPC.pdf

11:22 Towards Real-Time Simulation of Sphaleron Dynamics at Colliders

Sphaleron production in the Standard Model at high-energy particle collisions remains experimentally unobserved, with theoretical predictions hindered by its nonperturbative real-time nature. In this work, we investigate a quantum simulation approach to this challenge. Taking the $1+1$D $O(3)$ model as a protocol towards studying dynamics of sphaleron in the electroweak theory, we identify the sphaleron configuration and establish lattice parameters that reproduce continuum sphaleron energies with controlled precision. We then develop quantum algorithms to simulate sphaleron evolutions where quantum effects can be included. This work lays the ground to establish quantum simulations for studying the interaction between classical topological objects and particles in the quantum field theory that are usually inaccessible to classical methods and computations.

Speaker: Min Huang (高能所)

Sphaleron_on_QC.pptx

11:44 Semi-automatic Calculations of Multi-loop Feynman Amplitudes with AmpRed

Speaker: Wen Chen (华南师范大学量子物质研究院)

AmpRed_CEPC2025_WenChen.pdf

12:06 Top quark form factor

Speaker: Narayan Rana

CEPC25_Narayan.pdf

11:00 → 12:30 PID & Misc: 1

Zoom Link, ID:97990003364, Code:309122

Convener: XiaoLong Wang (Fudan University)

11:00 New particle identification subsystem and the space

Speaker: Zhonghua Qin (高能所)

ConsiderationOfCEPCRich-CEPCWorkshop-V2.pdf

11:15 Review on photosensors

Speaker: Peter Krizan (University of Ljubljana)

cepc-ws-2025-krizan.pdf

11:45 Development and production of aerogel radiators for Cherenkov detectors

Speaker: Evgeniy Kravchenko (Budker INP SB RAS/ Novosibirsk State University)

KravchenkoCEPC2025.pdf

12:10 MTD barrel timing detector at CMS

The High-Luminosity LHC upgrade will present unprecedented challenges, including intense radiation and up to 200 simultaneous proton collisions. To cope with this, the CMS experiment will deploy a new MIP Timing Detector (MTD) to precisely timestamp MIP particles. This contribution focuses on the MTD's Barrel Timing Layer (BTL), which is now transitioning from a successfully validated design to full-scale construction, highlighting its innovative crystal-based technology and assembly progress.

Speaker: Xiaohu Sun (Peking University)

MTDBarrel-CEPC-XiaohuSUN-CEPC2025NOV.pdf

11:00 → 12:30 TDAQ: 2

Zoom Link, ID:91076566347, Code:228773

Convener: Qidong Zhou (山东大学/Shandong university)

11:00 FPGA based RDMA and BEE readout

Speaker: Chang Xu (高能所)

广州报告_英文_1.pdf

11:15 LHCb TDAQ system

Speaker: Guoming Liu (South China Normal University)

LHCb_TDAQ_system_overview.pdf

11:35 LHCb HLT software and GPU algorithm

Speaker: Miroslav Saur (Lanzhou University)

saur_cepc_2025_11_09_LHCb_HLT.pdf

11:55 Progress of online process software frame for CEPC ref-detector

In high-energy physics experiments, online data processing plays an important role. Positioned between the readout of the front-end electronics and the disk, it reduces the vast raw data to a storable size through fast reconstruction and event filtering. Next-generation experiments such as the Circular Electron–Positron Collider (CEPC) impose even more stringent requirements on online data processing. Heterogeneous computing—coordinating different processors like CPUs and GPUs—can boost online data-processing capability and meet these higher demands. This report presents and describes a heterogeneous online data-processing framework designed for CEPC, aiming to improve online computing power through heterogeneous computing resources and thereby provide solid online data-processing support for the CEPC.

Speaker: Xu Zhang (IHEP)

online_framework.pdf

12:10 A Distributed In-Memory Cache Pool-Centered Online Computing Architecture for HEP

Meeting the data processing requirements of next-generation high-energy physics collider experiments, such as the Circular Electron-Positron Collider (CEPC), poses a significant challenge for data acquisition systems, particularly in the real-time triggering, online selection, and flexible processing of enormous event rates. Conventional online computing architectures based on static pipelines exhibit limitations in flexibility, scalability, and the rapid deployment of offline algorithms.

This report presents a novel data acquisition and online computing architecture centered around a distributed in-memory cache pool. By establishing a globally shared cache pool, this architecture decouples front-end electronics readout from back-end high-performance online processing modules, enabling asynchronous communication. A core scheduling system manages the full lifecycle of online processing algorithms and enables dynamic resource allocation and isolation. This design ensures system real-time performance and stability while significantly enhancing flexibility for algorithm updates and module integration, effectively supporting the direct migration and application of complex offline algorithms in the online environment.

The core components of this architecture have been fully developed. Notably, this design has been successfully deployed and validated within the ​​Large High Altitude Air Shower Observatory (LHAASO). Field tests confirm that the system fulfills real-time processing demands under extreme data throughput, demonstrating the architecture's effectiveness and engineering feasibility in addressing the future data challenges of large-scale facilities like CEPC.

Speaker: Hangchang ZHANG (IHEP，中国科学院高能物理研究所)

dhcp-CEPC-2511.pdf

12:30 → 14:00 Lunch break

14:00 → 18:00 Free time

Monday, 10 November

09:00 → 10:30 Accelerator: 11

Zoom Link, ID:93618001420, Code:427946

Convener: Pierre Vedrine

09:00 CEPC SC quadrupoles development plan in EDR and status （remotely）

Speaker: Yingshun Zhu (高能所)

CEPC superconducting quadrupoles development plan in EDR and status.pptx

09:18 CEPC MDI Cryomodule design status

Speaker: Xiangzhen Zhang (高能所)

09:36 CEPC/SppC compatibility

Speaker: Yiwei Wang (IHEP)

SPPC_lattice_design_and_compatibility_CEPCworkshop2025_v3.pptx

09:54 SppC high field magnet

Speaker: Qingjin Xu (高能所)

HTS Program Status at IHEP-CAS-Nov 10 2025.pptx

09:00 → 10:30 PID & Misc: 2

Zoom Link, ID:97990003364, Code:309122

Convener: Sajan Easo (STFC)

09:00 From Lab to Industry: Recent Progress on Key Performance of SiPMs with epitaxial quenching resistors

Speaker: Dejun Han (Beijing Normal University)

2025CEPC广州年会_韩德俊.pdf

09:30 R&D of MCP-PMT for single photon detection

Speaker: Ping Chen

Ping CEPC 2025.pdf

10:00 Studies with position-sensitive SiPM and MPT readout chip

Speakers: Mingkuan Yuan (Fudan University) , Xiyang Wang (Fudan university)

Studies with position-sensitive SiPM and MPT readout chip.pdf

09:00 → 10:30 QCD: 1

Zoom Link, ID:96812316331, Code:367916:

Convener: Manqi Ruan (IHEP)

09:00 Jet production at N3LO from e+e- colliders

With the public release of parton level event generator NNLOJET, antenna subtraction method has been playing an important role in the precision predictions of high energy colliders. The talk includes the latest development of the antenna subtraction method and its application to di-jet productions on electron-positron colliders with up to N3LO QCD corrections.

Speaker: Xuan Chen (Shandong University)

2025XuanChen_CEPC.pdf

09:22 Planar Property and Long-range Azimuthal Correlation in Electron-positron Annihilation

The 𝑒+𝑒− annihilation of unpolarized beams is free from initial hadron states or initial anisotropy around the azimuthal angle, hence ideal for studying the correlations of dynamical origin via final state jets. We investigate the planar properties of the multi-jet events employing the relevant event-shape observables at next-to-next-to-leading order (O(𝛼3𝑠)) in perturbative QCD; particularly, the azimuthal angle correlations on the long pseudo-rapidity (polar angle) range (Ridge correlation) between the inclusive jet momenta are calculated. We illustrate the significant planar properties and the strong correlations which are natural results of the energy-momentum conservation of the perturbative QCD radiation dynamics. Our study provides benchmarks of hard strong interaction background for the investigations on the collective and/or thermal effects via the Ridge-like correlation observables for complex scattering processes.

Speaker: Mr Yuesheng Dai (Shandong University)

09:44 Single inclusive hadron production in e+e- annihilation at N3LO in QCD

Single-inclusive hadron production in electron-positron annihilation (SIA) represents the cleanest process for investigating the dynamics of parton hadronization, as encapsulated in parton fragmentation functions. In this talk, I will present the analytical computation of QCD corrections to the coefficient functions for SIA at next-to-next-to-next-to-leading order (N3LO) accuracy based on arXiv:2503.20441.

Speaker: Prof. Tongzhi Yang (South China Normal University)

CEPC_SIAN3LO_TZY.pdf

10:06 Global Analyses of Collinear Fragmentation Functions from the NPC Collaboration

Fragmentation functions (FFs) are crucial non-perturbative inputs in quantum chromodynamics (QCD) for predicting hadron production cross sections in high-energy scattering processes. In this talk, we present recent progress on global fits of FFs by the Non-perturbative Physics Collaboration (NPC). Our analyses incorporate a comprehensive set of precision measurements, including data from the LHC, electron-positron collisions, and semi-inclusive deep inelastic scattering. We report results for both light charged and neutral hadrons, highlighting the improved constraints on FFs achieved through these global fits. We also discuss the impact of data from future lepton colliders on light hadrons fragmentation functions.

Speaker: Dr XiaoMin Shen (Institute of Modern Physics (IMP), CAS)

CEPC2025-XiaoMinShen-v2.pdf

09:00 → 10:30 Software: 2

Zoom Link, ID:91076566347, Code:228773

Convener: Xingtao Huang (Shandong University)

09:00 Status and Plan for the Simulation Software in CEPCSW

Speaker: Tao Lin (高能所)

lintao-202511-CEPC-workshop.pdf

lintao-202511-CEPC-workshop.pptx

09:18 CyberPFA: Particle Flow Algorithm for Crystal Bar ECAL

Speaker: Yang Zhang (高能所)

CyberPFA_CEPCWorkshnop2025.pdf

09:36 Particle Flow in the Future Collider Experiments

Speaker: Fangyi Guo

PF_in_colliders_CEPC.pdf

09:54 Event display and Interactive Visualization Tools for the CEPC

Speaker: YuJie Zeng (Sun Yat-Sen University)

Event display and Interactive Visualization Tools for the CEPC.pdf

10:12 Design and Updates of CEPC Computing Platform

Speaker: Xiaowei Jiang (高能所)

Design and Updates of CEPC Computing Platform.pdf

10:30 → 11:00 Coffee break

11:00 → 12:30 Accelerator: 12

Zoom Link, ID:93618001420, Code:427946

Convener: Eun-san Kim

11:00 CEPC auxiliary facilities and green energy technologies

Speaker: Jinshu Huang

11:18 CEPC sustainable development issues

Speaker: Rui Ge (IHEP)

CEPC sustainable development issues.pptx

11:36 DeepC Status

Speaker: Song Jin (IHEP，CAS)

DeepC status.pptx

11:54 Operation experiences of BEPCII and HEPS

Speaker: Daheng JI (高能所)

Operation experiences of BEPCII and HEPS_jidh.pptx

11:00 → 12:50 PID & Misc: 3

Zoom Link, ID:97990003364, Code:309122

Convener: Zhonghua Qin (高能所)

11:00 Software and simulation for Cherenkov detectors

Speaker: Luka Santelj (University of Ljubljana)

cepc2025_Santelj.pdf

11:30 FARICH+AI : experience with RECO/ID/FASTSIM

Speaker: Fedor Ratnikov (HSE University)

FARICH_251110_CEPC.pdf

11:50 Deep Learning Algorithm for dN/dx in TPC

Particle identification (PID) plays a crucial role in particle physics experiments. A groundbreaking advancement in PID involves cluster counting (dN/dx), which measures primary ionizations along a particle’s trajectory within a high granularity time projection chamber (TPC), as opposed to conventional dE/dx measurements. A high granularity TPC with a pad size of 0.5x0.5 mm2 has been proposed as the gaseous detector for the Circular Electron Positron Collider (CEPC) to achieve exceptional hadron identification, which is particularly vital for flavor physics studies.

One of the major challenges in dN/dx lies in the development of an efficient reconstruction algorithm capable of extracting cluster signals from 2D pixel readouts. Machine learning algorithms have emerged as state-of-the-art solutions for PID. To address this challenge, we have designed a sophisticated simulation software framework that incorporates detector geometry, gas ionization, electron drift and diffusion, signal amplification, and pixel readout to generate large datasets. A deep learning algorithm tailored for point cloud data has been developed, utilizing a graph neural network implementation of the point transformer. By training the neural network on a substantial dataset of simulated events, the particle separation power has improved by 10% to 20% for pions and kaons within a momentum range of 5 to 20.0 GeV/c, compared to traditional dN/dx reconstruction algorithm.

Speakers: Guang Zhao (高能所) , Dian Yu (Université Paris Cité (FR), Tsung-Dao Lee Institute (CN))

PID_CEPCWS251110.pdf

12:10 Unsupervised Machine Learning Algorithm for Heavy nuclei PID

Particle identification (PID) of cosmic‐ray nuclei using silicon strip detectors is employed in many space-born experiments, such as AMS-02, DAMPE, and HERD. However, the detector response exhibits strong dependence on the relative hit position between strips, and the nonlinear effects of front-end electronics under large charges make it difficult to establish explicit analytic expressions for the signal–charge relation. As a result, conventional heavy nuclei PID approaches often rely on external detector information to correct the cluster signals.

We present a novel unsupervised learning algorithm for heavy nuclei PID based on an AutoEncoder architecture. By introducing a newly designed histogram loss, our method enables direct learning of the high-dimensional cluster features obtained from real data without the need for labels. This approach allows simultaneous extraction of particle charge and hit position, demonstrating the potential of unsupervised learning in addressing long-standing challenges in learning high-dimensional physical information, such as Jet tag.

Speaker: Dexing Miao (ihep)

12:30 TORCH: a precision fast timing detector for low-momentum particle identification

Speaker: Rui Gao (University of Oxford)

TORCH2025_CEPC.pptx

11:00 → 12:48 QCD: 2

Zoom Link, ID:96812316331, Code:367916:

Convener: Xuan Chen (Shandong University)

11:00 Determination of the strong coupling constant $\alpha_s$ from inclusive semileptonic $B$ meson decays

We demonstrate the feasibility of determining the strong coupling constant, $\alpha_s$, from the inclusive semileptonic decay width of $B$ mesons. We express the semileptonic $B$ decay width as a function of $\alpha_s(5\mathrm{\,GeV})$, the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$, $b$- and $c$-quark masses in the $\overline{\mathrm{MS}}$ scheme. We fit $\alpha_s(5\mathrm{\,GeV})$ to current world averages of the $B^{\pm}$ and $B^{0}$ semileptonic decay widths. This yields $\alpha_s(5\mathrm{\,GeV}) = 0.245 \pm 0.009$, corresponding to a 5-flavor extrapolation of $\alpha_s(m_{Z}) = 0.1266 \pm 0.0023$. The primary uncertainty contributions arise from the uncertainty on the perturbative expansion and the value of $|V_{cb}|$. Future advancements including higher-order perturbative calculations, and precise measurements of $|V_{cb}|$ and $B$ decay widths from upcoming $B$ and $Z$ factories, could enable this method to determine $\alpha_s(m_{Z})$ with a competitive precision of $\Delta\alpha_s(m_{Z}) \sim 0.0018$. This precision is comparable to the current accuracy of $\alpha_s(m_{Z})$ measurements from $\tau$-lepton decays, which is regarded as the most precise experimental approach.

Speaker: Yuzhi Che (IHEP)

广州_CEPCWS.pdf

11:22 Production of Tcc via photon-photon fusion at CEPC

Within a phenomenological diquark fragmentation model, we study the production of doubly charmed tetraquark Tcc via photon-photon fusion at electron-positron colliders. The production of Tcc is divided into two steps: the perturbative production of heavy (cc)-diquark and its nonperturbative hadronization. It is found that it is promising to observe the tetraquark Tcc via photon-photon fusion process both at CEPC and ILC. We find that the cross sections are sensitive to constituent charm quark mass of diquark, and they also have strong dependence on the hadronization models.

Speaker: Jun Jiang (山东大学)

TccProductionCEPC.pdf

11:45 Studying Bell nonlocality of light quarks and new physics effects in fragmentation hadrons at lepton colliders

Speaker: Bin Yan (IHEP)

QE_quarks.pdf

12:06 From UV to IR, tracking quantum information loss at colliders

Understanding decoherence during the evolution from high-energy (UV) to low-energy (IR) scales is a critical challenge for the new frontier of quantum information science at colliders. In this talk, I will present a novel framework that treats Renormalization Group (RG) flow itself as the engine of decoherence. By combining Soft-Collinear Effective Theory (SCET) with open quantum system techniques, we demonstrate that RG evolution constitutes a quantum channel where the scale, not time, drives a Markovian loss of information. Applying this to $e^+e^-\to \ell^+\ell^-$, we derive the first analytical prediction for entanglement suppression from final-state radiation. This work provides an essential tool for future precision quantum measurements and offers a new, operational perspective on the Renormalization Group.

Speaker: Dingyu Shao (Fudan University)

12:30 → 14:00 Lunch break

14:00 → 15:45 Plenary: 3

Zoom Link, ID:93618001420, Code:427946

Convener: Haijun Yang (Shanghai Jiao Tong University)

14:00 Indications for new Higgs bosons at the electroweak scale

Speaker: Andreas Crivellin (U)

CEPC2025plenary.pdf

14:25 New particle discovery potential

Speaker: Juraj Klaric

Klaric_NPDP_CEPC2025_Guangzhou.odp

Klaric_NPDP_CEPC2025_Guangzhou.pdf

14:50 The Linear Collider Facility proposal and the global Linear Collider Vision

Speaker: Jenny List (DESY)

jlist_LCVision_CEPC_251111_v1.pdf

15:20 Accelerator advancements for HEPS construction and BEPC II upgrade

Speaker: Yi Jiao (高能所)

2015-11-CEPC2025-Accelerator advancements for HEPS construction and BEPC II upgrade.pptx

15:45 → 16:15 Coffee break

16:15 → 18:10 Plenary: 4

Zoom Link, ID:93618001420, Code:427946

Convener: Jianchun Wang (IHEP)

16:15 Recent progress in iron-based superconducting materials toward applications

Speaker: Yanwei Ma (IEE, CAS)

CEPC2025-Ma-251109.pptx

16:40 FPGA-based real-time reconstruction for HEP experiments

Speaker: Giovanni Punzi (University of Pisa)

Punzi_CEPC_101125.pdf

17:05 Plasma Wakefield Accelerator: A Roadmap towards Future

Speaker: Wei Lu (IHEP, CAS)

CEPC25-weilu.pptx

17:30 IHEP high power and high efficiency klystron development

Speaker: Zusheng Zhou (IHEP)

CEPC klystron development.pptx

17:55 Closing

CEPC2025_Closing.pdf