The 2024 International Workshop on the High Energy Circular Electron Positron Collider

22 Oct 2024, 00:00 → 27 Oct 2024, 18:00 Asia/Shanghai

Hangzhou Platinum Hanjue Hotel

Jianchun Wang (IHEP) , Hongbo Zhu (Zhejiang University) , Miao He (IHEP)

The 2024 international workshop on the high energy Circular Electron Positron Collider (CEPC) will take place at Hangzhou, Oct 23-27, 2024, co-hosted by Zhejiang University and Institute of High Energy Physics, CAS.

The CEPC study group has released  the Technical Design Report (TDR) on accelerator, and is working towards the Engineering Design Report (EDR). The group also plans to release  a TDR of a reference detector in 2025. This workshop intends to gather scientists around the world to study the physics potentials of the CEPC, pursue international collaborations on optimization of the accelerator and the detectors, deepen R&D work of critical technologies. Furthermore, industrial partnership for technology R&D and industrialization preparation will be explored.

The workshop program consists of plenary, parallel and poster sessions. All plenary presentations are invited talks. All posters are chosen from the abstract submissions. Presentations in the parallel sessions are from both sources. The workshop encourages participation, especially from graduate students and postdocs. Top posters will receive awards, selected by a committee that consists of the SPC members, the session conveners and the local organizers.

If you are wondering about the entrance visa, please visit https://indico.ihep.ac.cn/event/20099/ which is also accessible through the registration page. Payment will be made on site. The registration deadline is Sept 30, 2024. 

The deadline for abstract submission has been extended to Sept 15, 2024.

For assistance please contact cepcws2024@ihep.ac.cn.

CEPC.jpg

Group Photo.jpg

Information_to_the_driver.jpg

会议证明（中文 1000）.pdf

会议证明（中文 2000）.pdf

Tuesday, 22 October

12:00 Registration in the Hotel Hall

Wednesday, 23 October

Plenary: 1

Zoom Link, ID:85910938851, Code: 848529

Convener: Hongbo Zhu (Zhejiang University)

1 Welcome

Speaker: Prof. Kai Wang (Zhejiang University)

2 BSM physics at a Tera-Z and Higgs factory

Speaker: Tiann-Tevong You (King's College London)

TevongYou.pdf

3 Overview of CEPC

Speaker: Xinchou LOU (高能所)

10:30 Coffee break

Plenary: 2

Zoom Link, ID:85910938851, Code: 848529

Convener: Yuhui Li

4 Prospects on ILC and other LC projects

Speaker: Taikan Suehara (ICEPP, The University of Tokyo)

241023-cepcws-lcstatus-suehara.pdf

241023-cepcws-lcstatus-suehara.pptx

5 Status of FCC

Speaker: Frank Zimmermann (CERN)

FCC-CEPC-WS-Oct2024.pptx

6 The ECFA Detector R&D Roadmap and DRD Collaborations

Speaker: Thomas Bergauer (OEAW-HEPHY Vienna)

2024-10-23_CEPC2024_Bergauer_DRD-Europe_Bergauer.pdf

Accelerator: 1

Zoom Link, ID:84479508720, Code:925544

Convener: Makoto Tobiyama（remote） (KEK Accelerator Laboratory)

7 On the challenges of future colliders

Speaker: Maria Enrica Biagini (INFN-LNF)

Biagini_CEPC_WS_2024.pdf

8 CEPC accelerator EDR status

Speaker: Jie GAO (IHEP)

CEPC Accelerator EDR -V3-(CEPC workshop parallel)-J. Gao.pdf

9 CEPC collider ring beam dynamics EDR plan and status

Speaker: Yiwei WANG (IHEP)

CEPC collider ring beam dynamics EDR plan and status (CEPC 2024).pptx

10 CEPC first tune operation required machine tuning (including orbit corrections and sextupoles and luminosity ramping scenarios

Speaker: Bin Wang (IHEP)

20241023_CEPC_workshop_BinWang_v2.pdf

20241023_CEPC_workshop_BinWang_v2.pptx

11 The status of accelerator design program kit: APES

Speakers: Yuan Zhang (IHEP, Beijing) , Zhiyuan Liu

APES-CEPC workshop-20241023.pptx

BSM: 1

Zoom Link, ID:85910938851, Code: 848529

12 Testing Bell inequality through h → τ τ at CEPC

Speaker: Kai Ma (Shaanxi University of Technology)

13 One-point correlators of conserved and non-conserved charges in QCD

Speaker: Minho Son

14 LAYCAST: A proposed detector for long-lived particle searches at the CEPC

Speaker: Ye Lu (Wuhan University of Technology)

LAYCAST a proposed detector for long-lived particle searches at the CEPC.pdf

LAYCAST： a proposed detector for long-lived particle searches at the CEPC.pptx

15 Presenting results from experimental searches for new physics

Speakers: Andrew Fowlie, Andrew Fowlie (Nanjing Normal University)

bayes_factor_surface_fowlie.pdf

https://arxiv.org/abs/2401.11710

CIPC: 1

Zoom Link, ID:87170162344, Code:625716

Convener: 张玉包 (高能所)

16 Accelerating Equipments Development at HERT

Speaker: 宋迺斌（生产部经理）

Accelerating Equipments Development at IHEP&HERT 2024-song.pdf

17 东方超导射频超导腔制造技术提升及产业化

Speaker: 赵伟东（工程师） (18095218212)

超导腔制造技术提升与产业化（英文）-超导公司—20241020.pdf

18 安徽海泰科加速器超导高频相关部件研制汇报

Speaker: 李荣（副总经理）

安徽海泰科电子科技有限公司介绍-20241023s.pptx

19 中科富海大型低温制冷机研究与应用进展

Speaker: 王广海(技术中心副主任)

国产低温制冷机的应用.pdf

20 紫明低温技术及核心设备

Speaker: 孙浩瀚（总经办主任）

紫明低温技术及核心设备.pdf

Calorimetry: 1

Zoom Link, ID:81317080254, Code:103003

21 DRD-on-Calorimetry (DRD6) Overview

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

hangzhou.roberto.drd6.2024.10.23.pdf

22 DRD6 WP1 on Sandwich Calorimeters with Embedded Electronics

Speaker: Adrian Irles (IFIC - CSIC/UV)

20241023_CEPC_DRD6_WP1.pdf

23 DRD6 WP2: Liquified Noble Gas Calorimeters

Speaker: Fares Djama (CPPM Marseilles)

AllegroEcal_Djama.pdf

24 DRD6 WP3: Optical Calorimeters

Speaker: Michaela Mlynarikova (CERN)

DRD6 WP3_ Optical calorimeters.pdf

15:30 Coffee break

Accelerator: 2

Zoom Link, ID:84479508720, Code:925544

Convener: Frank Zimmermann（ remote） (CERN)

25 ATF2 and perspective of ATF3

Speaker: Philip Burrows（ remote） (John Adams Institute, Oxford University)

ATF_CEPC_Oct2024.pdf

26 CEPC booster and damping ring (DR) EDR plan and status

Speaker: Dou WANG (IHEP)

Booster - wangd-v2.pptx

27 CEPC impedance budget update in EDR (including collimators) and limitation to luminosities

Speaker: Na Wang (IHEP)

CEPC impedance budget update__NaWang_CEPCworkshop20241023.pptx

28 Beam tracking simulations on resistive wall instability in the CEPC collider ring using mbtrack2-cuda

Speaker: Keon Hee KIM

KH KIM CEPC Workshop.pptx

29 CEPC MDI EDR plan and status

Speaker: Sha BAI （remote） (高能所)

CEPC MDI EDR plan and status.pptx

30 Operation experiences of BEPCII and HEPS

Speaker: Daheng JI (高能所)

Operation experiences of BEPCII and HEPS1.pptx

BSM: 2

Zoom Link, ID:85910938851, Code: 848529

31 The Right-Handed Slepton Bulk Region for Dark Matter in Generalized No-scale F-SU(5) with Effective Super-Natural Supersymmetry

Speaker: Tianjun Li (Institute of Theoretical Physics, Chinese Academy of Sciences)

CEPC-10-23-2024.pdf

32 Predictive Type-II seesaw extension of NMSSM from AMSB/GMSB and LFV constraints

Speaker: Fei Wang (Department of Physics, ZhengZhou University)

CEPC-wangfei.pdf

33 Dark matter searches at CEPC

Speaker: Peng-fei Yin (IHEP)

241023 Dark matter searches at the CEPC.pdf

34 Overview of DM and neutrino physics at CEPC

Speaker: Yongchao Zhang (Southeast University)

DM_neutrino_CEPC2024.pptx

35 Prospects for light exotic scalar measurements at the e+e- Higgs factory

Speaker: Aleksander Filip Zarnecki (Faculty of Physics, University of Warsaw)

zarnecki_exscalar_cepc2024_2.pdf

CIPC: 2

Zoom Link, ID:87170162344, Code:625716

Convener: 李荣 (安徽海泰科电子科技有限公司)

36 昆山国力CEPC 高功率高效率650MHz/800kW连续波速调管研制进展

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

2024 CIPC分会-CEPC 高功率高效率650MHz800kW连续波速调管研制进展-王少哲.pdf

37 无锡华康固态放大器的现状及未来发展

Speaker: 何圣侃（总经理） (无锡市华康广播电视设备厂)

CEPC2024-无锡华康.pptx

38 北京大有科能固态脉冲调制器

Speaker: 王聪聪（副总）

科大有能-加速器会议介绍.pdf

39 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） (高能所)

综合辐射监测系统在大科学装置应用方案.pdf

40 上创超导二代高温超导材料应用研究进展及未来产业

Speaker: 菅洪彬（总助/部长）

杭州CEPC会议-20241023上创超导.pdf

Calorimetry: 2

Zoom Link, ID:81317080254, Code:103003

41 CEPC ScW-ECAL and AHCAL prototypes and beamtest studies

Speaker: 洪滨 刁 (中国科学技术大学)

The Development and Commissioning of High Granular Scintillator-based.pdf

42 Development of a Highly Granular Crystal ECAL for CEPC

The discovery of the Higgs boson filled the last missing block of the Standard Model. After this, the precision measurement of this particle became a frontier scientific problem, because it can be used as a probe to study physics beyond the Standard Model. Such scientific target requires unprecedented jet energy resolutions. For the electromagnetic calorimeter (ECAL), the required boson mass resolution (BMR) and energy resolution are 4% and $\left ( 30 \text{–} 40 \right ) \% / \sqrt{E \ \mathrm{[GeV]}}$ respectively. Such requirements can be met with sampling ECAL designs, viz. SiW- and ScW-ECAL, which can achieve an energy resolution of $\left ( 15 \text{–} 20 \right ) \% / \sqrt{E\ \mathrm{[GeV]}}$. Such value is sufficient for most physical processes; yet for $H \to \gamma \gamma$ process, the width of the invariant mass strongly depends on the energy resolution of photons. Hence, homogeneous ECAL concepts based on crystals and SiPMs have been proposed, and are expected to further improve BMR and energy resolution to 3% and $\left ( 3 \text{–} 4 \right ) \% / \sqrt{E \ \mathrm{[GeV]}}$ respectively.

The novel design of ECAL for CEPC features long BGO crystal bars (typically $1 \times 1 \times 40 \, \mathrm{cm}^3$). For consecutive layers, they are aligned orthogonally with read-out on both ends of the crystal bars, hence improving granularity, reducing the number of read-out channels and minimising the amount of dead material in layers. For the Technical Design Report (TDR), the mechanical structure has also been developed. Recently, the overall structure is still being optimised.

Currently, the performance of SiPMs and crystals are being studied. Specifically, the linearity and dynamic range of SiPM response have been obtained with optical simulation and laser test, the uniformity of BGO crystal bars has been obtained with radiation source scanning, and the time resolutions of long crystal bars have been studied. Furthermore, beam test experiments have been carried out at CERN and DESY respectively, providing valuable data for studying the performance of the crystal modules. Further studies of the intrinsic properties of SiPMs and crystals are still ongoing at present.

Speaker: Ji-Yuan Chen (SJTU)

20241023-CrystalECAL-JiYuanChen.pdf

43 Beamtests of the small-scale crystal module for future high-granularity crystal ECAL

The future Higgs Factories, e.g. the Circular Electron Positron Collider (CEPC) aiming at precise measurements of the Higgs, W/Z bosons, and the top quark, have stringent requirements on the calorimetry systems to achieve unprecedented jet energy resolutions. A novel high-granularity crystal electromagnetic calorimeter (ECAL) has been proposed for an excellent electromagnetic energy resolution of $2-3~\%/\sqrt{E(\mathrm{GeV})}$. To evaluate the EM performance of the crystal ECAL and identify critical issues on the system level, a small-scale BGO crystal module with $12\times12\times24$ $\mathrm{cm^3}$ dimensions has been designed and produced for beamtest activities. The BGO crystals have been tested with the radioactive source for calibrations. The specialised PCBs and 3D-printed support structures have been designed to meet the requirements of the crystal module. Beamtest experiments utilising muon, pion, and electron beams have been carried out at the CERN T9 and DESY TB22 beamlines to investigate the EM performance. Geant4 simulations, in conjunction with a dedicated digitisation framework, have been employed to understand the beamtest results and further validate the performance of the crystal ECAL.

Speaker: Baohua Qi (IHEP)

20241022_Beamtests of the small-scale crystal module for future high-granularity crystal ECAL.pdf

44 Beam-induced background studies for CEPC calorimeters

Speaker: Weizheng Song (Institution of High Energy Physics)

Beam-induced background studies for CEPC calorimeters.pdf

45 Dual-readout calorimetry R&D activities in Asia

Speakers: Hwi Dong YOO (Yonsei University) , Hwidong Yoo (Yonsei University)

HDYOO_CEPC_10232024.pdf

18:30 Receiption (18:30 - 21:00)

Poster: Group A - Accelerator and beam

Conveners: Dou WANG (IHEP) , Hai Chen (Zhejiang University) , Miao He (IHEP) , Tao LIN (高能所) , XUHAO YUAN (IHEP, Beijing) , Xuan Chen (Shandong University)

46 === Group A posters === This file contains all posters in the group

Speaker: Miao He (IHEP)

GroupA.pdf

47 An External Injected Drive-witness Bunch Pair Merge System with Femtosecond Timescale Jitter

Beam-driven plasma-wakefield accelerator (PWFA) transform the energy from the leading drive bunch to a trailing witness bunch. The separation of the two bunches is in the order of 100 fs. In order to obtain high transformer ratio and long-distance acceleration PWFA, we need to precisely control the separation of the drive and witness bunch. We propose a new scheme to merge two electron bunch within an ultra-short distance. The two-electron beam with different energy can be merge by one common dipole. However, energy jitter could cause time jitter for the separation between the two bunches. In order to suppress the time jitter, we designed a high order isochronous merge system, in which the separation time jitter caused by energy jitter can be limited to femtosecond timescales. Besides, we take control of the coherent synchrotron radiation (CSR), which can affect both time jitter in the longitudinal phase space and emittance growth in the transverse phase space.

Speaker: 为 李 (中国科学院高能物理研究所)

CEPC_Poster_LiWei.pdf

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

In modern particle accelerators, multiple superconducting cavities are often driven simultaneously by one high-power klystron, thereby reducing the cost of the power supplies. The CEPC RF system contains 96 cryomodules for 650 MHz 2-cell cavities. Each cryomodule contains six 650 MHz 2-cell cavities, driven by a single high-power klystron. This approach significantly reduces the cost of the power supply but introduces several challenges for high-precision control of superconducting cavities, such as gradient differences due to individual cavity variations, frequency offsets caused by Lorentz force detuning, and the calibration of vector sum of amplitudes and phases for multiple cavities. This paper introduces the design of a MicroTCA.4 based Low-Level Radio Frequency (LLRF) control system for multi-cavity control, which will be used for the horizontal testing of the CEPC 650MHz superconducting cavities. Based on the vector-sum control principle, the system utilizes IQ sampling, feedforward-feedback control, and other techniques, eventually achieved high-precision amplitude and phase control and frequency tuning of six superconducting cavities.

Speaker: Wenbin Gao (IHEP)

CEPC2024_wokshop_poster_GaoWenbin.pdf

49 Design and High-Power Test of the High Efficiency RF Power Source Test Stand

The high-power RF power source system is the energy acquisition of particle acceleration, and is the key devices. Taking the CLIC/FCC project planned in Europe and the CEPC project planned in China as an example, the total power requirement of the RF power system is about 110 MW, which is a huge energy consumption. Therefore, it is important to explore the ways to maximize the energy conversion efficiency of RF power systems for future advanced projects.
The Institute of High Energy Physics (IHEP) has developed a high power test stand (HPTS) for high-power superconducting RF power source systems, which is used for explore topics in high-efficiency klystrons, multi-beam klystrons, multi-stage depressed collection (MSDC), energy recovery, and high-power reliability research and high power conditioning tasks. And it is also a prototype validation of the CEPC megawatt PSM high-voltage power supply. This article provides a detailed introduction to the design and implementation of the platform. The highlight of this HPTS is that it achieves full output range of high-voltage duty cycle from pulse to continuous wave. In continuous wave applications, the high voltage ripple/stability is improved from the traditional PSM power supply's 1% level to the 0.1% level, achieving an order of magnitude improvement. Compatible with pulse mode applications, the pulse width can be adjusted from 0.5ms to DC, with leading edge, flat top, and repetition stability indexes reach the level of specially designed long pulse modulators. As a result, the newly developed power supply can provide a flexible high-power test environment for the research and development of CEPC high-efficiency klystron tubes. Not only effectively reducing the probability arcing events in newly processed klystron, but also synchronizing the entire RF conditioning process, reducing consumption, and improving energy utilization efficiency. The prototype was completed in 2021 and passed a 200kW resistive load test.
In 2024, full-scale power experiments were completed for CEPC high-efficiency 800kW/650MHZ klystron loads. Its RF power reaches up to 800kW, which also verifies the effectiveness of the proposed hybrid modulation high-voltage power supply and lays an excellent foundation for the subsequent high-efficiency program of RF power source.

Speaker: Dr Jingdong Liu (高能所)

Design and High-Power Test of the High Efficiency RF Power Source Test Stand.pdf

50 Design and high power test of 650MHz/800 kW high efficiency klystron for CEPC

The 650MHz/800kW CW klystron is an important component of the RF power source for the Circular Electron Positron Collider (CEPC). In order to reduce the energy demand and operating costs of the CEPC, the high efficiency klystron is developed at Institute of High Energy Physics , which is aiming to increase the efficiency of the klystrons to above 80%. In March 2020, the first prototype klystron, using a second harmonic cavity, achieved output efficiency of around 65%. To further increase the efficiency of the klystrons to around 75%, the second prototype klystron adopts a combination of lower perveance and the core stablization method (CSM). Currently, this prototype klystron has been finished high power test. The test results show that the output power and efficiency have reached 803kW and 78%, respectively.

Speaker: 欧正 肖 (高能所)

Design and high power test of 650MHz 800 kW high efficiency klystron for CEPC.pdf

51 Development of 1.2 Mega-Watt P-band Travelling Wave Resonant Ring

High power microwave devices, such as ceramic windows and waveguide valves, are critical components in accelerators, where safety and reliability are paramount. To ensure their safe operation, these devices must undergo rigorous high-power testing. The Traveling Wave Resonant Ring (TWRR) is an economical and efficient device used for such testing. The Institute of High Energy Physics (IHEP) is currently designing a TWRR at the P-band frequency to support the development of klystrons. The TWRR's main components include a directional coupler, observation window, load and cooling system. This TWRR is capable of testing at 1.5 times the rated power of an 800-kW klystron, significantly reducing the risk of the window being penetrated during operation.

Speaker: 凡予 王 (高能物理研究所)

2024CEPC_Poster_Wang Fanyu.3pptx.pdf

52 Superconducting quadrupole magnets in the interaction region of BEPCII-U and CEPC

Superconducting quadrupole magnets in the interaction region of BEPCII-U and CEPC

This presentation will present the superconducting quadrupole magnets in the interaction region that have been manufactured for the BEPCII Upgrade (BEPCII-U) project and then describe the superconducting quadrupole magnets in the interaction region that are being designed for the Circular Electron Positron Collider (CEPC).

The BEPCII-U project is an upgrade and renovation project based on BEPCII. The aim is to increase the highest beam energy from the current 2.47 GeV to 2.8 GeV. Based on this requirement, the existing combined superconducting magnets in the collision area of BEPCII cannot meet the design requirements, so a new magnet has to be developed to increase the magnetic field strength. The aim of the development of these magnets is to increase the magnetic field gradient of the SCQ from 18.7 T/m to 25 T/m, while maintaining other coil performance indicators, with the overall size of the magnet remaining unchanged. We have successfully wound several superconducting quadrupole magnets which have been shown by magnetic field measurements to meet the design requirements and will be used in the BEPCII-U project.

As the study of superconducting quadrupole magnets in the interaction region of the CEPC at the Higgs factory enters the CEPC engineering design report (EDR) phase, the design of superconducting quadrupole magnets in the interaction region has become one of the key challenges. The CEPC Technical Design Report (TDR) proposed a basic design scheme utilizing Cos2θ coils with iron core shielding, which meets the physical requirements. However, the iron core increases the magnet’s weight, imposing a substantial burden on the mechanical support system. To address this issue, this study investigates the design of ironless core magnets. Two primary schemes are considered: a Cos2θ coil magnet design equipped with an external correction coil, and a Canted Cosine Theta (CCT) magnet coil design that can be modified by the parametric equations.

Speaker: Jieru Geng (IHEP)

75-J. Geng.pdf

53 Design and development of CEPC control system

Design and development of CEPC control system towards EDR is introduced, including key issuses, manpower and current progress.

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

Design and development of CEPC control system.pdf

54 Preliminary design of energy recovery scheme for high-power

Based on the high efficiency klystron scheme of circular electron positron collider (CEPC), the depressed collector design is proposed to improve the overall efficiency of RF power source. The depressed collector technology has been applied in low power microwave electronic vacuum devices such as TWT and TV communication klystrons. The velocity of electrons entering the klystron collector is scattered, and it is difficult to use the depressed collector to sort the velocity of electrons. This paper will carry out a detailed theoretical analysis of the depressed collector and determine its basic design scheme for CEPC high efficiency klystron. In order to verify the klystron energy recovery scheme, an energy recovery verification device is designed. DGUN and CST codes are used for optimization design of verification device beam. ANSYS thermal analysis is carried out on the depressed collector to determine the electron gun and depressed collector design scheme. The verification device is expected to be completed by the end of the year to carry out high-power experiments.
Keyword: depressed collector, klystron, energy recovery, electron gun

Speaker: yu liu (Institute for High Energy Physics)

CEPC_Poster2024_LiuYu .pdf

55 CEPC Megawatt-level High Power Density High Voltage Power System

The cost of large particle accelerator devices is expensive (up to billions), and the operating energy consumption is huge (hundreds of megawatts). Green, environmental economics and sustainability are hot topics in accelerator research. For the CEPC CDR/TDR, a high-efficiency RF power source system is planned. This system adopts a 1-to-1 scheme, necessitating 96 sets of 650MHz 800kW high-efficiency klystrons and PSM (Pulse Step Modulation) high-voltage power supply systems.
This paper introduces a novel design scheme for high-voltage power supplies (HVPS) and explores the feasibility of using a 1-to-2 or 1-to-4 configuration, where a single megawatt high-power HVPS could drive multiple klystrons. The proposed design features high power density and hybrid modulation methods. The key advantages of this scheme include:
1 ) Cost Reduction: The new design is expected to cut project costs by 50%, making it a more economical choice for large-scale accelerator projects.
2 ) Improved Reliability: By increasing the Mean Time Between Failures (MTBF), the system's overall reliability is significantly enhanced.
3 ) Enhanced Performance: The power supply performance for continuous-wave applications is improved, ensuring more stable and efficient operation.
4 ) Additionally, this new HVPS scheme can be utilized for power factor correction in large power grids. It offers a reactive power compensation capacity ranging from 2.19 to 5.475 MVar, potentially reducing annual operating expenses by 15.33 to 38.32 million RMB.
The proposed design scheme not only supports the green, energy-saving, and sustainable development of large accelerators like CEPC but is also applicable to future projects such as the Compact Linear Collider (CLIC) and the Future Circular Collider (FCC).

Speaker: Dr Jingdong Liu ( Institute of High Energy Physics, CAS)

Megawatt-level High Power Density High Voltage Power System2.pdf

56 Design and simulation of Electron gun and Magnet of C-Band 80MW klystron for CEPC LINAC

After the discovery of the Higgs boson at LHC, Chinese scientists have proposed a circular electron-positron collider (CEPC) and a super proton–proton collider (SPPC). The main component of the CEPC accelerator complex is the collider ring, booster, damping ring and Linac which has a circumference of 100 kilometers. The Linac's primary high-power RF components consist of 33 units of 80 MW S-band (2860 MHz) klystrons and 236 units of C-band (5720 MHz) klystrons. This paper describes the design and simulation of the complete electron gun and electromagnet for 80 MW C-band klystrons of CEPC Linac. At an acceleration potential of 425 kV, a space charge beam current of 425A is achieved with an average cathode loading of less than 9.0 A/cm2. It has been calculated that the maximum surface electric field at the high voltage ceramic seal and beam optics is less than 23 kV/mm and 4.80 kV/mm, respectively. With an average beam radius of 5.40 mm, the electron beam is successfully transported to the interaction cavity with a beam ripple rate of around 5.0%. The 3-D CST simulation validates and finds agreement with the results of the 2-D DGUN, and POISSON simulations.

Corresponding author at: Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
Supported by: Yifang Wang ten thousand project
Corresponding author E-mail address: zhouzs@ihep.ac.cn (Z.-S. Zhou).

Speaker: NOMAN HABIB (高能所)

CEPC poster.pdf

57 Phase and Amplitude Calibration of the Sub-harmonic Buncher for the High Energy Photon Source Linac

The High Energy Photon Source (HEPS) Linac is a normal conducting electron linear accelerator capable of producing high bunch charge beam. Its bunching system includes two Sub-harmonic buncher (SHB), one pre-buncher, one buncher, and one accelerating structure. To achieve high bunch charge beam, it is often necessary for the electron gun to operate with high current and long pulse, which implies strong bunch length compression and significant space charge effects.

The SHB is commonly used in the low-energy section for longitudinal bunching to increase the bunch charge. The phase and amplitude of the SHB is crucial for achieving high-quality electron beam in Linac. This paper presents a method for calibrating the phase and amplitude of the SHB using the time-of-flight technique, and experiments were conducted based in the HEPS Linac and employing two Beam Position Monitors (BPMs).

According to the simulations, we found that bunch length and space charge effect have a significant impact on the results, and we propose corrective measures to address them. In beam experiments, the method for BPM signal is crucial. To enhance experimental efficiency, we propose a data processing method called the truncated averaging technique that eliminates the need for corrective measures, which has been validated through both simulations and experiments, yielding outstanding results.

This paper presents detailed insights into both the simulation and experimental procedures.

Speaker: 中天 刘 (高能所加速器中心)

CEPC2024海报.pdf

58 Design of S-band high efficiency klystron

To reduce energy consumption and cost has become a prime objective of the development and operation of high energy particle accelerators. RF sources are major energy consumption components of any RF system for the particle colliders. The 30 GeV injector linear accelerator (LINAC) for the CEPC (Circular Electron and Positron Collider) requires S-band klystrons with higher efficiency to reduce energy consumption and cost. In this paper, two novel bunching method, including COM (Core Oscillation Method) and BAC (Bunching Alignment and Collecting), are applied to the BEPCII (Beijing Electron Positron Collider) S-band klystron. These methods increase the efficiency of klystron from 45% to 55%, therefore increasing the output power to 80 MW with the same operation voltage. The preliminary optimization design is completed with 1-D disk model based AJDISK code and further checked by 2-D code EMSYS and 3-D CST Studio Suite. The density modulation of electron injection is improved by selecting a suitable cavity string structure and thereby to optimize electron bunching. Further improvement in the RF conversion efficiency of the klystron is also planned and is in line with a requirement to go green

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

CEPC2024_wangya.pdf

59 Design of periodic permanent magnet for S-band high efficiency klystron

Improving the efficiency of the klystron can significantly reduce the operational costs of particle accelerators. This paper investigates the use of permanent magnets in klystrons, aiming to create a design that minimizes energy usage while maintaining performance. The focus of this study is on the design of a periodic permanent magnet (PPM) for S band high efficiency klystron. In addition to the innovative magnetic field configuration, the study includes the design of a new output cavity. This cavity is optimized to match the phase of both the outer and inner beam components, which is crucial for maximizing output power and efficiency. The development of a PPM S-band klystron represents a significant step forward in klystron design, offering a more efficient and cost-effective solution for high-power applications. This design reduces power consumption while maintaining or even improving performance, contributing to the broader goals of energy efficiency and cost reduction in accelerator technology.

Speaker: Han Xiao (IHEP)

2024CEPCWS_XiaoHan.pdf

60 Study on Arc Protection for CEPC High-Voltage Direct Current Long-Distance Transmission

The CEPC high-voltage direct current (HVDC) power supply and the klystron are connected via a long-distance HVDC cable. When an arc short circuit occurs in the klystron, the energy generated by the discharge of the distributed capacitance in the long-distance transmission cable can directly damage the klystron. To address this, a high-voltage direct current long-distance transmission arc protection device has been developed. This device has a voltage rating higher than 120 kV and, when an arc short circuit occurs in the klystron, triggers the Crowbar device to instantly bypass and discharge the energy. The response time of the device is less than 5 microseconds, and the energy is limited to within 10 joules. This paper will analyze the discharge energy of the distributed capacitance in long-distance cable transmission based on the layout of the CEPC HVDC power supply and the klystron, establish a circuit model, conduct system simulations and energy calculations, and systematically analyze the design principles and key technologies of the arc protection device.

Speaker: Fei Li (IHEP)

CEPC_Poster2024_LiFei.pdf

61 Integrating Machine Learning in Bunch-by-Bunch Feedback Systems for CEPC

For accelerators like CEPC, which have extremely large storage rings, there is a significant issue with beam instability, making it necessary to employ feedback systems to suppress these instabilities. The damping time that feedback system can provide includes the time for signal acquisition and processing. In traditional bunch-by-bunch feedback systems, the filter processes signals that require data collection over multiple turns. The effect of this data acquisition time on the damping time is not prominent in smaller circumference storage rings, but it can become a major issue in the CEPC, potentially resulting in damping times comparable to the instability growth times. By utilizing appropriate machine learning techniques, it is possible to train on a large dataset of beam oscillation signals to directly compute the feedback signals required for the beam, significantly shortening the data acquisition time, achieving faster damping times than traditional feedback systems, and even realizing single-turn feedback. This project creatively integrates machine learning with the design of the bunch-by-bunch feedback system, exploring new possibilities for the feedback systems required for ultra-large storage rings.

Speaker: Di Yin (IHEP)

CEPC_POSTER.pdf

62 Design of Collimator Control System for PWFA

Speaker: Shutao Zhao (高能所)

Poster ID349.pdf

63 CEPC carbon footprint and CO2 reduction optimization

Speaker: Dou WANG (IHEP)

poster-carbon.pdf

Poster: Group B - Silicon detector

Conveners: Dou WANG (IHEP) , Hai Chen (Zhejiang University) , Miao He (IHEP) , Tao LIN (高能所) , XUHAO YUAN (IHEP, Beijing) , Xuan Chen (Shandong University)

64 === Group B posters === This file contains all posters in the group

Speaker: Miao He (IHEP)

GroupB.pdf

65 CMOS Strip Chip Simulation with RASER

The CMOS strip sensor is a key component of the CEPC Inner Tracker. By extending the Python-based framework RASER (RAdiation SEmiconductoR), we have simulated the complete CMOS Strip Chip (CSC). First, we evaluated its electrical performance, including capacitance, leakage current at operating voltage, and the strip's weighting potential. Next, we simulated the CMOS readout integrated circuit, which includes components such as the amplifier, comparator, and buffer. Finally, we simulated the response of the CSC as a detector using laser and radioactive sources.

Speaker: 森 赵 (湖南师范大学)

CEPCWS_Chenxi_Sen_Xin.pdf

66 Beam Background Study for the CEPC Silicon Tracker

The hit rate study for the CEPC silicon tracking system, induced by beam background processes such as pair production, will impact irradiation, data rates, and the design of the detector, particularly for the CEPC operating in high-luminosity Z-pole mode. In addition to beam properties, the hit rate is influenced by factors such as the distribution of materials near the interaction point, detector materials, sensor granularity, and hit response. This presentation will provide a detailed analysis of the hit rate for the CEPC silicon tracker using simulations with the CEPC software CEPCSW.

Speaker: Mr Zhan Li (IHEP)

poster_Zhan_vFinal.pdf

67 Design and Optimization of the CEPC Tracking System

The Circular Electron Positron Collider (CEPC) is specifically designed for in-depth studies of Higgs, W, and Z bosons, as well as heavy flavor particles. The precision tracking system is pivotal for the success of these physics studies. This presentation will delve into the software tools include fast simulation and full simulation as well as optimization standards that have been meticulously selected, and applied it to achieve best performance. The presentation will showcase the impact of these optimizations on key performance indicators such as momentum resolution, tracking efficiency, and the robustness of the track fitting process.

Speaker: qinglin Geng

B088_CEPC_poster-ID88_GengQinglin.pdf

68 AMSL0 Ladder Production

The AMSL0 upgrade project will add a 2-plane silicon stripe track detector layer to the original 9-layer detector of AMS. The sensitive area of new layer is about 8 square meters in total. This new layer will triple the acceptance of cosmic rays of the AMS and significantly improve its performance in identifying heavy ions. The sensitive area planes are composed of 72 ladders, including 40 ladders with 12 sensors, 16 ladders with 10 sensors, and 16 ladders with 8 sensors. All the ladders need to be produced, and then assembled to the whole plane, so the production of ladders is an important part. In order to ensure good spatial resolution of the detector, the lateral variance of the sensor positions of a ladder should be less than 5 microns.

Ladder production is based on a customized gantry. Gantry head can achieve micron-level movement accuracy in four dimensions: x, y, z and θ. It includes a vacuum to suck up a pick-up tool, which is used for moving a sensor. Two camera with micron-level precision on the gantry head are used to identify the fiducial marks to measure the position of sensor. All of the above procedures are operated through a custom software. This poster will show the ladder production details and results.

Speaker: Mr 沁泽 李 (高能所)

poster_Qinze.pdf

69 Test of CMOS chip using 55nm process

The CEPC plans to utilize a high spatial resolution, low-material, fast-readout, large-area, and cost-effective silicon-based tracker system. CMOS technology is a promising solution. Compared to hybrid silicon pixel sensors, CMOS processes enable smaller sensor sizes while maintaining a lower material budget. CMOS technology is also a potential candidate for future upgrades to other experiments, such as the LHCb Upstream Tracker.

Unlike many CMOS processes that require modifications to achieve sufficient signal generation, commercially available high-resistance wafer-based High Voltage CMOS (HVCMOS) is intrinsically radiation-hard and offers substantial capacitance for signal acquisition. While HVCMOS may have higher noise and power consumption compared to small-electrode CMOS, these factors are manageable for large-area trackers. Recent advancements in the HVCMOS production process at domestic foundries make it commercially customizable.

We will present promising test results from preliminary CMOS sensors, including those from the 55nm process (COFFEE), COFFEE1, and COFFEE2.

Speaker: Zhiyu Xiang

CEPCposter_zhiyu_v2.pdf

70 HVCMOS (COFFEE) Simulation

Technology Computer-Aided Design (TCAD) simulations were conducted on High Voltage CMOS (HV-CMOS) sensors with varying substrate resistivities. The simulations investigated how changes in substrate resistivity affect leakage current, breakdown voltage, the depletion region, and the distribution of high electric field areas within the sensor. The effects of pixel gap and p-stop on capacitance were evaluated, with simulation results agreeing with experimental measurements. Furthermore, Allpix2 simulations provided insights into the sensor's response to Minimum Ionizing Particles (MIPs), facilitating an analysis of signal collection and charge sharing phenomena across different substrate resistivities.

Speaker: Mx Jianpeng Deng (Zhejiang University)

post_final.pdf

71 MAPS-based Upstream Tracker for The LHCb Phase-II Upgrade

The LHCb experiment is planning a phase-II upgrade to accommodate the expected peak luminosity of L= 1.5×10^34 cm^(-2) s^(-1). The upgrade is scheduled to be implemented during the long shutdown 4, starting around the year 2032. The technical design report for the upgrade framework was released in 2022.
The Upstream Tracker, positioned before the LHCb magnet, plays a critical role in enhancing online reconstruction speed, reducing ghost tracks, and improving the reconstruction efficiency of long-lived particles. It will be upgraded from a silicon microstrip detector to a monolithic silicon pixel detector. This poster will introduce R&D efforts in various aspects, such as the development of simulation and reconstruction software within the LHCb software framework, the design of the detector using existing technologies, performance evaluations through simulation for detector optimization, and the exploration of potential detector technologies, including small-electrode and large-electrode types.

Speaker: 吉 彭 (高能所)

pengji_v3.pdf

72 Beam Test For The AMS-02 Layer0 Tracker Upgrade

The Alpha Magnetic Spectrometer (AMS-02) detector operates on the International Space Station. It performs high precision measurements of cosmic ray composition and fluxes, searches for antimatter and dark matter. To increase the detection acceptance and improve its heavy ion identification power, the AMS collaboration plan to add a new layer (L0) of silicon tracker on top of AMS-02. The detector consists of 2 planes, 72 silicon strip detector ladders. Each ladder has 8, 10, or 12 silicon strip detector sensors (SSDs) connected in serial, producing an effective strip length of about 1 meter. The total sensitive area is about 8m2.

In order to study the detector ladder in cosmic rays and particle beams, and calibrate the L0 tracker with particle beams before launching to the space, a beam monitor has been produced. The monitor consists of 12 single-SSD modules with a readout electronics system similar to that of the L0 detector. The beam monitor alone had been used in testbeams using electron beam at IHEP to characterize the SSD, which was custom designed for the AMS L0 upgrade. The beam monitor has also been used to test prototype ladders using proton, muon and heavy ion beams at CERN.

In this poster the detailed performance of the beam monitor and AMSL0 prototype ladder will be described. We use beam monitors to obtain heavy nuclei recognition performance up to zinc nuclei (Z=30), with a charge resolution of ~0.1 and a spatial resolution better than 2 um. This allows for the study of the ladder's charge resolution and position resolution performance.

Speaker: Dexing Miao (ihep)

dexing_cepcws2024.pdf

73 Transition-Edge Sensor Microcalorimeter Development for Particle Physics at IHEP

The transition-edge sensor (TES) is a type of thermal equilibrium superconducting detectors that offers excellent energy resolution, a wide dynamic range, and high quantum efficiency. We are developing TES microcalorimeters for Neutrino-less double beta decay (0𝜈ββ) experiments and high energy astrophysics missions.
In regular nuclear double beta decay (2𝜈ββ), two electrons are emitted along with two antineutrinos. In contrast, 0𝜈ββ emits only electrons, without accompanying neutrinos or antineutrinos. This process necessitates that the neutrino to be a Majorana particle, meaning the neutrino is its own antiparticle. To date, this decay has not been experimentally observed and the Majorana particle theory remains hypothetical. Confirmation of 0𝜈ββ would directly support the Majorana theory, which extends beyond the Standard Model. Such measurements demand extremely low noise, achievable with low-Tc TESs. We fabricate our TESs with AlMn alloy, the transition temperature of which can be finely tuned through annealing temperature and duration. We have successfully produced devices with superconducting transition temperatures with a span from 10 mK to 600 mK. We are now integrating the TES with a lithium molybdate crystal, and will characterize its spectral performance in the near future.
TESs can also be used for space X-ray/𝛾-ray applications to study sciences including the dynamics of matter around black holes and neutron stars, galaxy evolution, and physical phenomena under extreme gravitational and magnetic conditions, etc. We plan to build a dedicated space telescope to measure the 511 keV gamma-ray emission from the Galactic Center with an energy resolution of E/∆E > 1000, using a large Laue focusing mirror to provide sufficient sensitivity. Compared with the existing 511 keV space projects, this project is expected to have sensitivity improvement of about one or two orders of magnitude. This measurement can help finding the origin of positron and its distribution in the center of the Milk Way. We have designed a stacked TES detector comprising six layers of arrays, each with 256 TES pixels. The total detection area is approximately 10 cm2, and the quantum efficiency at 511 keV is 93% with the six-layer stack configuration. In the coming year, we will commence the fabrication of these gamma-ray TES detectors.

Speaker: Daikang Yan (IHEP)

Poster.pdf

74 The Installation and operation of the Upstream Tracker for the LHCb upgrade

The Large Hadron Collider (LHC) began its third run, known as Run 3, in 2023. During this phase, the LHCb detector operates at a higher instantaneous luminosity (Linst = 2 × 10³³ cm⁻² s⁻¹), which is five times greater than in Run2, and has transitioned to a full 40 MHz software trigger system. This increases the demands on the detectors significantly. To address these challenges, LHCb has undergone a major upgrade, replacing nearly all of its subsystems. The all-software trigger relies on real-time readout, reconstruction, and selection of data. Fast and efficient track reconstruction is particularly crucial. The Upstream Tracker (UT), a new silicon microstrip detector located upstream of the dipole magnet, replaces the old tracker TT and is a critical component of the LHCb tracking system. The UT consists of four silicon microstrip planes and reads out with 128-channel SALT ASICs. Installed in LHCb in 2023, the UT has recently begun physics data-taking globally after a few months of commissioning. This poster will cover the installation and commissioning of the UT and will also include the operation during data-taking.

Speaker: Dr Mingjie Feng (IHEP)

mingjie_v2.pdf

75 Design of AC-LGAD for CEPC OTK

The CEPC plans to deploy a time-of-flight (ToF) detector using AC-LGAD technology to advance its flavor physics research capabilities. AC-LGAD detectors with 100% fill factor, are designed to deliver high-precision measurements of both spatial coordinates and timing for detected particles.

AC-LGADs for CECP will be implemented as strip-type, single-layer structures and will be installed in both the barrel and endcap regions. The sensors in the barrel region will be the longest of their kind globally, while the endcap sensors will feature a non-parallel strip design. IHEP's expertise in LGAD technology will be crucial for optimizing aspects such as radiation hardness, gain layer design, and epitaxial layer growth.

The AC-LGAD-based ToF detector is expected to achieve a time resolution of 50 picoseconds and a spatial resolution of 10 micrometers in the bending direction. Simulation results indicate that this design will greatly enhance the separation of kaons from pions and kaons from protons within the 1-2 GeV energy range. The incorporation of this advanced detector will provide the CEPC with four-dimensional detection capabilities—offering precise timing and positional information for charged particles—thus significantly improving measurement precision and broadening the scope of flavor physics research.

Speaker: Weiyi Sun

CEPCStripLgadPoster2.pdf

76 HVCMOS (COFFEE2) Design

Sub-100nm processes are becoming a critical trend in the development of HV-CMOS pixel detector technology. To evaluate the impact of in-pixel electronics design on HV-CMOS pixel sensor performance at these advanced process nodes, we have designed and submitted a prototype chip named COFFEE2, fabricated using a 55nm HV-CMOS process. This chip features a pixel array of 32 rows by 20 columns, divided into three regions, each with distinct in-pixel amplifier and comparator structures. Additionally, the chip includes a bandgap reference, row/column configurations, and digital-to-analog converters (DACs) integrated into the peripheral circuitry surrounding the pixel matrix. We will present detailed electronic designs, simulation results, and preliminary test results.

Speaker: 乐怡 李 (中国科学院高能物理研究所（IHEP）)

CEPC_hangzhou_poster_lileyi.pdf

77 Geometric Optimization Simulation of the CEPC Vertex Detector

The identification of heavy-flavored quarks and $\tau$ leptons is an important physics goal of the Circular Electron Positron Collider(CEPC). The vertex detector of the CEPC is capable of obtaining precise track parameters of charged particles in the vicinity of the Interaction Point to reconstruct the decay vertex of short-lived particles. The CEPC vertex detector adopts the CEPC-MOST2 structure, which is a cylindrical barrel structure consisting of three layers from the inside to the outside with the ladder as the detection unit. The two sides of the ladder are affixed with a pixel-type sensor, TaichuPix-3, which has a single-point resolution of $5 \mu m$, and the center is supported by carbon fiber. The carbon fiber, along with flexible circuit boards affixed to both sides as a support structure. To achieve low material mass, the ladder of layers at different radii covering $\theta=8.1°$ adopts varying thicknesses of flexible circuit boards and support structures. The impact parameter is used to characterize the performance of the vertex detector. Currently, based on the radius of the beam pipe of $10~mm$ in the CEPC-TDR, the position of the first layer of the CEPC vertex detector has reduced to $12.5~mm$, and the radius of the outermost layer of the vertex detector is set at $44.5~mm$. The average material budget for the beam pipe, the first layer of the vertex detector, and the second layer of the vertex detector are $0.162\%~X_0$, $0.565\%~X_0$, and $0.676\%~X_0$, respectively. The outgoing particles $\mu^-$ momentum is greater than $\mathrm{15\,GeV/c}$, the resolution of the impact parameter resolution is less than $3~\mu m$, and the performance exceeds that of the CDR-full simulation.

Speaker: 田园 张

CEPC2024poster.pdf

78 Simulation Results of CEPC OTK with CEPCSW

The AC-LGAD technology has been selected for use as the Time-of-Flight (ToF) detector and outer tracker for the Circular Electron-Positron Collider (CEPC). This ToF detector is essential for flavor physics at the CEPC, particularly for distinguishing kaons from pions in the low-energy range. The AC-LGAD-based ToF and outer tracker will be positioned between the TPC and ECAL, covering an area of 90 m².

The geometric model of the LGAD detector has been completed and integrated into CEPCSW. Using the DD4HEP toolkit, this model incorporates all relevant features and aligns with the existing geometry. Calculations have been conducted to assess the hit rate based on the simulation results with the integrated geometry.

Speaker: Dian Yu (Tsung-Dao Lee Institute)

poster.pdf

79 Full Simulation and Geometry Creating of CEPC Tracker

The tracking system of the fourth conceptual detector at CEPC consists of a silicon pixel vertex detector, a silicon tracker of HV-CMOS and LGAD, and a time projection chamber (TPC). 
The tracking system plays an important role in tracks reconstruction and PID.
It's necessary and urgent to validate the momentum resolution, physics performance of the tracking system and even PID capacity of Inner Tracker Endcap (ITKE), with a preliminary layout design by the full simulation tool implemented in CEPCSW.
The momentum resolution of different sub-tracker by incidence angle scanning has been done. The preliminary result of the recoiled Higgs was used to verify tracker's physics performance. Simple-designed double-layer silicon endcaps were implemented in CEPCSW to check the silicon's ability of PID.
And now, the staggered staves geometry of ITK Barrel (ITKB) has been created in CEPCSW by DD4hep to better serve the simulation.
The ITKE's geometry will be recreated after the new design completed as well.

Speaker: Xiaojie 啸捷 Jiang 姜 (IHEP)

Jxj_posterV2.1_cepcws2024_800mm.pdf

Poster: Group C - Other detectors and software

Conveners: Dou WANG (IHEP) , Hai Chen (Zhejiang University) , Miao He (IHEP) , Tao LIN (高能所) , XUHAO YUAN (IHEP, Beijing) , Xuan Chen (Shandong University)

80 === Group C posters === This file contains all posters in the group

Speaker: Miao He (IHEP)

GroupC.pdf

81 Radar, a DAQ software framework

Radar is a software framework for high energy physics experiment data acquisition and online processing. The LHAASO DAQ and JUNO DAQ systems are developed based on RadarV1.0 and RadarV2.0, respectively. The data volume of CEPC is two orders of magnitude higher than that of JUNO, which puts forward higher requirements for online data processing capabilities. With reference to the data processing capability of JUNO, the CEPC DAQ developed based on RadarV2.0 may require a cluster consisting of thousands of CPU servers. In order to improve the single node computing performance, we plan to adopt the heterogeneous computing scheme with FPGA + GPU + CPU, and are developing the high throughput and high bandwidth heterogeneous data acquisition and online processing framework for CEPC- RadarV3.0.

Speaker: 叙 张 (高能所)

posterV1.2.pdf

82 Development of Al-stabilized superconductor for the CEPC Detector Magnet

A huge superconducting magnet is proposed for the future detector of Circular
Electron Positron Collider (CEPC) at the Institute of High Energy Physics,Chinese Academy of Sciences (IHEP,CAS) .The design field of CEPC detector magnet is 3 Tesla, the coil length is 9.15m, and the free bore is 7.07m.An aluminium stabilized Rutherford type conductor is developed for the CEPC detector magnet.This paper presents R&D process and the main features of the Al-stabilized conductor.

Speakers: Ling Zhao (高能所) , Dr Menglin Wang

Development+of+the+Aluminum+stabilized+superconductor+for+CEPC1.pdf

83 Title: Study of Synchrotron Background in the CEPC Accelerator

Abstract: The Circular Electron Positron Collider (CEPC) presents a significant opportunity for advancing high-energy physics research, but its operation also brings about challenges related to synchrotron background radiation. This study focuses on characterizing and mitigating the synchrotron background produced within the CEPC accelerator environment. Synchrotron radiation, primarily generated by the bending and focusing of electron and positron beams, poses potential risks to both detector performance and beam stability.

In this work, we perform comprehensive simulations using advanced particle tracking and radiation modeling tools -- CEPCSW, to quantify the synchrotron radiation flux and energy distribution across MDI regions of the CEPC.

Our findings aim to enhance the understanding of synchrotron radiation behavior in the CEPC and contribute to the development of effective mitigation strategies, ensuring optimal performance and longevity of the accelerator and its detectors.

Speaker: 彦邦 唐 (IHEP)

46.pdf

84 Applications Of Blockchain Technology Distributed Computing In High Energy Physics

The HEP software community has identified scalability, complexity, and cost as barriers to advancing high-performance computing in high-energy physics. We intend to address these issues by pulling technology from other domains, such as artificial intelligence, traditional financial technology, web3, and blockchain. By combining computational systems from other domains with existing HEP software, the HEP software community can share costs, pool resources, and aggregate computation power with other computational domains addressing these issues.

In this talk, we will describe the current status and design of our blockchain system which leverages existing open source software technology and web3 for generalized high-performance computing and its application to high energy physics and AI. Our computational infrastructure using comprises a decentralized blockchain system that passes messages between computational nodes, implemented as docker/OCI containers. We use an the end-to-end principle to place policy controls at the endpoints, drastically simplifying computational complexity and removing barriers to international resource sharing between institutions and professional domains.

To support HEP workflows, we are integrating the streaming network with a computational node that uses the Key4Hep framework to include software commonly used in HEP, such as ROOT, Gaudi, and Podio. We have designed the system to allow easy integration with software-as-a-service systems such as AI providers such as ChatGPT or OpenLllama. We have designed the system to be scalable both upward,
allowing the creation of computational networks of the scale of the Bitcoin computation network, and downward, allowing the creation of simple ad hoc distributed computation systems. An open-source prototype of our work is available on GitHub, and we are seeking users and developers from the HEP community.

Speaker: Joseph Wang (Laguna Labs)

cepc-blockchain-poster.pdf

85 Conceptual mechanical design of CEPC detector magnet

A large-scale low-temperature superconducting magnet is proposed for the future detector of Circular Electron Positron Collider (CEPC) at the Institute of High Energy Physics, Chinese Academy of Sciences (IHEP,CAS). The center magnetic field of the magnet is 3 Tesla, the length, inner and outer diameter of the magnet is 9.05 m, 7.07 m and 8.47 m，respectively. The length, inner and outer diameter of the coil is 8.15 m, 7.3 m and 7.82 m，respectively. The weight of the cold mass is about 140 t. This poster presents the mechanical design of the support structure of the cold mass and the cryostat of the magnet.

Speaker: Mr Zhilong Hou (高能所)

Conceptual mechanical design of CEPC detector magnet-Poster.pdf

86 Status and performance of LumiBelle2 in the 2024 beam operation of SuperKEKB

LumiBelle2 is a fast luminosity monitoring system designed to do fast luminosity feedback and machine tuning and beam parameters studies for SuperKEKB. It uses sCVD diamond detectors placed in both the electron and positron rings to measure the Bhabha scattering process at vanishing photon scattering angle. Two types of online luminosity signals are provided, Train-Integrated-Luminosity signals at 1 kHz as input to the dithering feedback system used to maintain optimum overlap between the colliding beams in horizontal plane, and Bunch-Integrated-Luminosity signals at about 1 Hz to check for variations along the bunch trains. Vertical beam sizes and offsets can also be determined from collision scanning. This paper will describe the design of LumiBelle2 and report on its performance in the 2024 beam operation of SuperKEKB.

Speaker: UNKNOWN 李萌

LumiBelle2_poster.pdf

87 Studies of TPC detector prototype for future lepton collider experiments

A global community of physicists specializing in Lepton Collider Time Projection Chambers (TPC) is working to realize an exceptional physics program at the energy-frontier, particularly for electron-positron collisions in the International Linear Collier (ILC) and the Circular Electron Positron Collider (CEPC). A large TPC prototype, tested in a 1.0 T magnetic field, accommodates up to seven identical Micro Pattern Gaseous Detector (MPGD) readout modules. This prototype has been studied using a 5 GeV electron beam at DESY. Several successful beam test experiments have measured key performance metrics, such as the drift velocity, spatial resolution, and the dE/dx resolution, using different readout concepts (GEM, Resistive Micromegas and GridPix) with a monolithic cooling plate in 2-phase CO$_{2}$.

In the update CEPC Physics and Detector Technology Design Report (TDR), the TPC is described as having a cylindrical drift volume with an inner radius 0.6 m, an outer radius of 1.8 m, and a half-length of 2.9 m. This design significantly enlarges the tracking acceptance (cos$\theta$ ~0.98). The TPC can provide up to thousands of 3-D space points, with a single hit resolution of approximately 100 $\mu$m in the $r-\phi$ plane. There are two options for the readout structure: pad and pixel, both of which are promising technologies, especially at the high luminosity Z-pole.

In this talk, we will present the track reconstruction performance results and outline the next steps for developing pad/pixelated TPC technology for future lepton colliders.

Speaker: Mr Xin She (IHEP,CAS)

CEPC2024Poster_PixelTPC01.pdf

88 Artificial Intelligence Applied Researches on Online Monitoring System

The online monitoring system is an essential component of the data acquisition system, delivering swift, efficient, and comprehensive real-time monitoring for the readout chain. However, traditional online monitoring systems primarily rely on preset rules for data selection and inspection, which are unable to cope with complex operating conditions and large data volumes in real time. There are also problems that rely on manual monitoring and inspection, which is prone to omissions and inefficiency. This limitation makes it difficult for monitoring systems to accurately predict abnormal situations, severely impacting production efficiency and equipment safety. To address these challenges, the application of artificial intelligence technology has become a choice. A solution that combines machine learning and large language model technology for application on online monitoring systems has been designed to enhance the accuracy and efficiency of data inspection. Machine learning algorithms, through learning from historical data, can adaptively adjust monitoring models to more accurately identify potential risks. Meanwhile, by leveraging the inferential capabilities of large language models combined with past expert experience, the system can perform root cause analysis and provide real-time alerts, enhancing predictive capabilities to handle complex monitoring scenarios and provide more valuable references. The detailed research and application of the system will be presented in this poster.

Speaker: 水涵 张 (高能所)

Poster66_zhangsh.pdf

89 Preliminary design consideration for CEPC fast luminosity feedback system

Future large high-luminosity electron-positron collid- ers such as Circular Electron Position Collider (CEPC), and Future Circular Collider (FCC-ee) require nanometre-sized beams at the interaction point (IP). The luminosity is very sensitive to the beam orbit drifts at the IP. It is essential to have a fast luminosity feedback system at the IP to maintain optimum beam collision conditions and prevent a luminosity degradation due to orbit drifts in the presence of mechanical vibrations and dynamical imperfections.We considered two possible methods for this purpose for CEPC: one based on measurements of the luminosity and the other based on measurements of the beam orbits around the IP. In this paper, we present the preliminary design consideration for a fast luminosity feedback system at the IP of CEPC.

Speaker: Dou WANG (IHEP)

CEPC_poster-LiMeng.pdf

90 Studies on the Dynamic Range of SiPMs with High Pixel Densities

The future Circular Electron-Positron Collider (CEPC) is a large-scale experimental facility designed to enable precise measurements of the Higgs boson, electroweak physics, and the top quark. For the CEPC detector system, a highly granular crystal electromagnetic calorimeter is proposed, targeting an electromagnetic energy resolution of less than 3%. This calorimeter features a homogeneous structure with long crystal scintillator bars as the active material and Silicon Photomultipliers (SiPMs) as the preferred photon sensors. Simulations indicate that the energy deposited by a single crystal could reach up to 30 GeV, corresponding to over 300,000 photoelectrons per side based on the light yield of BGO crystals. This necessitates that the SiPMs maintain a linear response across a very wide input range, making high pixel density a critical requirement to avoid saturation.

This study explores the characteristics of SiPMs with varying pixel densities, focusing on their performance across a broad dynamic range. Utilizing a comprehensive experimental setup that combines laser sources and photomultiplier tubes (PMTs) for precise light intensity calibration, we evaluated SiPMs with pixel counts up to 244,719 and pixel sizes as small as 6 micrometers. To complement these experimental findings, we developed a model to simulate the SiPMs' responses under different lighting conditions, incorporating key parameters such as pixel density and photon detection efficiency. The simulations closely matched the experimental results for laser light, revealing similar trends of nonlinearity. For BGO scintillation light, the simulations—accounting for multi-firing effects of pixels—showed significantly higher photon counts compared to the laser-based simulations. Moreover, the simulated responses derived from this research provide a method to correct for SiPM saturation effects, ensuring accurate measurements in high-energy events even when using SiPMs with a limited number of pixels.

Speaker: Zhiyu Zhao (TDLI/SJTU)

Poster_SiPMDynamic_ZhiyuZhao.pdf

91 Studies on timing performance of BGO crystal scintillator

The future Circular Electron-Positron Collider (CEPC) is envisioned as a large-scale Higgs factory. For the CEPC detector system, a highly granular crystal electromagnetic calorimeter has been proposed to provide 5D information, incorporating x, y, z, E, and t dimensions. This calorimeter features a homogeneous structure with long crystal scintillator bars as the active material, with BGO and SiPM being the preferred components. Time information plays an increasingly critical role in calorimeters. It not only helps to distinguish pile-up effects but also aids in particle identification, shower reconstruction, and enhances the energy resolution of the calorimeter. Consequently, optimizing and understanding the timing performance of this detector design is essential.
The timing resolution of the detector unit, which consists of a BGO crystal and two SiPMs, was optimized using various methods through cosmic ray experiments. The best time resolution at the 1-MIP level for a 40 cm BGO crystal coupled with a specific SiPM is around 1 ns. In beam tests conducted in 2023, the timing resolution of BGO crystal bars under high-energy electron showers was studied, achieving a resolution of 200 ps for signals exceeding 12 MIPs. The study also found that shorter crystals exhibited better time resolution, and the long crystal bars demonstrated good timing resolution uniformity. Additionally, simulations were conducted to investigate the impact of various factors on timing resolution, such as crystal length, decay time, and light yield, as well as the timing characteristics of new materials like BSO.

Speaker: Zhiyu Zhao (TDLI/SJTU)

Poster_BGOTiming_ZhiyuZhao.pdf

92 CEPC stereo ECAL muon momentum reconstruction

This research focuses on the particle reconstruction algorithm of the stereo crystal electromagnetic calorimeter for the Circular Electron Positron Collider (CEPC). The stereo crystal structure, as one of the design options for the CEPC electromagnetic calorimeter, possesses unique properties. It not only provides information on the energy deposition location but also reconstructs 3D cluster information from 2D plane information with minimal dead zones. Taking muon momentum reconstruction as an example, based on the CEPC Software (CEPCSW) framework, this study simulates and reconstructs single muon events emitted from the particle gun. For the first time, this research analyzes the energy deposition distribution of single muon events within the stereo crystal electromagnetic calorimeter up to 10 GeV, allowing for a direct determination of the particle's charge information. Furthermore, based on the motion of charged particles in a magnetic field, the relationship between particle deflection and transverse momentum is derived. The resolution of this particle momentum reconstruction algorithm is less than 20%, laying a foundation for subsequent clustering algorithms.

Speaker: UNKNOWN 郭蕾

CEPCWS_Poster301_LeiGuo.pdf

93 Design for the Spiral Barrel Yoke of CEPC Detectors: A Self-Supporting Installation Scheme

Leveraging the spiral structure of the CEPC detector barrel yoke, we have designed an innovative installation scheme. This scheme comprises three primary components: the barrel yoke module, end flange, and barrel yoke support structure. By dispensing with the auxiliary installation structure traditionally used, the barrel yoke can be installed utilizing its own end flange, thereby streamlining the installation process. The design of the end flange also significantly enhances the structural strength of the barrel yoke. Furthermore, this installation scheme minimizes material waste and optimizes the use of underground space.

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

Design for the Spiral Barrel Yoke of CEPC Detector-A Self-Supporting Installation Scheme.pdf

94 Comparing Event Generators for Radiative Bhabha Interaction at CEPC

Small-Angle Bhabha Scattering is a traditional process used for high-precision luminosity measurement at electron-positron colliders, known for its clean event signature and large cross section. The Circular Electron Positron Collider (CEPC) is a Higgs factory that will produce millions of HZ events at √s=240GeV, and 0.7 trillion Z bosons at the Z-pole energy. In order to improve precision on measurements of Standard Model processes, the luminosity systematic with an accuracy of 〖10〗^(-4) is required. This study focuses on the measurement of radiative Bhabha interaction using the event generators ReneSANCe and BHLUMI, aiming to achieve a systematic uncertainty of 0.01% for the Bhabha cross-sections. The radiative photons from NLO processes are compared in terms of momentum and opening angles relative to the electrons, considering the luminometer acceptance at CEPC. Our study suggests that the detection of radiative Bhabha events is a viable approach to achieving a precision of 〖10〗^(-4) for the luminosity measurement at CEPC.

Speaker: Jiading Gong (Jilin University)

Poster_Jiading_Gong.pdf

95 Fast Luminosity diamond monitor for CEPC

Speaker: 家梁 张 (Nanjing University)

c351_Fast Luminosity diamond monitor for CEPC_poster.pdf

Thursday, 24 October

Accelerator: 3

Zoom Link, ID:84479508720, Code:925544

Convener: Maria Biagini (INFN-LNF)

96 A historical review on TTC

Speaker: Carlo Pagani (INFN-MI)

Pagani_a historical review on TTC_CEPC2024.pptx

97 Recent Development of SRF Technologies Worldwide: Highlights from TTC2023 meeting at Fermilab

Speaker: Eiji Kako（remote） (KEK)

Kako, Highlights of TTC2023-Fermilab for CEPC2024Workshop, 2024 Oct. 23.pdf

98 CEPC SRF (both collider & booster) EDR plan and status

Speaker: Jiyuan Zhai (IHEP)

20241024_SRF_CEPC workshop Hangzhou.pptx

99 CEPC SC quadrupoles development plan in EDR and status

Speaker: Yingshun Zhu (高能所)

CEPC SC quadrupoles development plan in EDR and status.pptx

100 CEPC cryogenic system EDR plan and status

Speakers: Mei Li (remote), Rui 葛锐 (IHEP)

CEPC cryogenic system EDR plan and status-V2-short--24th, Oct.(1).pptx

CIPC: 3

Zoom Link, ID:87170162344, Code:625716

Convener: 史轶君 (宜兴市诚鑫辐射防护器材有限公司)

101 项目过程虚拟仿真研究综述与CEPC相关进展

Speaker: Prof. 王佳斌 (华侨大学)

CEPC仿真报告-w.pptx

102 API激光跟踪仪在加速器领域的应用

Speaker: 杨余潜(中国区总经理) (美国自动精密工程公司)

103 HTC及真空阀门介绍

Speaker: 刘长江（副总）

2024 SHTC简报 CEPC会议.pptx

104 四川宇天真空科技有限公司的发展与优势

Speakers: 陈本富（董事长）, 张帆（副总）

四川宇天真空科技有限公司的发展与优势-B版s.pptx

105 RGA在超高真空和加速器领域的应用

Speaker: 刁立臣(总经理） (浦发真空)

Calorimetry: 3

Zoom Link, ID:81317080254, Code:103003

106 Glass Scintillator Hadron Calorimeter for CEPC

Speakers: Sen Qian (高能所) , 伯祥 俞 (高能所)

CEPC-GS-HCAL-2024-Oct24-CEPCWS.pdf

107 Glass Scintillator R&D activities and highlights

Speaker: 高 唐 (cjlu)

CEPC-GS-10.23HZ-2.pdf

108 CMS High Granularity Calorimeter (HGCAL) Upgrade

Speaker: Gobinda Majumder (Tata Institute of Fundamental research, Mumbai, India)

cepc_cms_hgcal.pdf

109 PicoCal: fast-timing and radiation-tolerant ECAL for LHCb Upgrade II

Speaker: 之洋 原 (北京大学)

PicoCal fast-timing and radiation-tolerant ECAL for LHCb Upgrade II.pdf

EW & tt: 1

Zoom Link, ID:85910938851, Code: 848529

110 Precision measurements at the Z resonance

Speakers: 志均 梁 (中国科学院高能物理研究所) , 梁志均 LIANG Zhijun

CEPC-ewk-20241024-v2.pdf

111 The GRIFFIN project and precision calculations at the Z resonance

Speaker: Ayres Freitas (University of Pittsburgh)

cepc24_freitas.pdf

112 Reducing Feynman Integrals using Blade

Speaker: 文浩 武

WenHaoWu20241022WICEPC.pptx

113 Top quark mass measurements at the tt threshold with CEPC

Speaker: Zhan Li (IHEP)

TopMass_Zhan.pdf

114 Optimizing Entanglement and Bell Inequality Violation in Top Anti-Top

Speaker: 焜 程 (北京大学物理学院)

OptimalBell_CEPCWorkshop.pdf

10:30 Coffee break

Accelerator: 5

Zoom Link, ID:84479508720, Code:925544

Convener: Carlo Pagani (INFN-MI)

115 PAL-XFEL LINAC Operation

Speaker: Garam Hahn

20241024 Recent Progress of PAL-XFEL Operation.pdf

116 CEPC Linac EDR plan and status

Speaker: Jingru Zhang (高能所)

CEPC Linac EDR plan and status.pptx

117 CEPC Magnets (both collider & booster)

Speaker: Wen Kang, Mei Yang

CEPC Magnets.pptx

118 CEPC Vacuum system EDR plan and status

Speaker: Yongsheng MA (高能所)

CEPC Vacuum system EDR plan and status-workshop.pptx

119 CEPC powers sources in EDR

Speaker: Bin Chen (高能所)

20241024 CEPC Magnet Power Supply System in EDR.pptx

CIPC: 4

Zoom Link, ID:87170162344, Code:625716

Convener: 王佳斌 (华侨大学)

120 科烨公司介绍与优势技术

Speaker: 龙风（副总经理） (合肥科烨电物理设备制造有限公司)

科烨公司介绍与优势技术2024.10.22.pdf

121 国内磁铁产业介绍和上海克林发展与优势

Speaker: 汤桐生（总经理） (chnkelin)

国内磁铁产业介绍和上海克林发展与优势.pdf

122 钢研总院磁屏蔽产业概述及在高能物理中应用

Speaker: 杨锋（主任）

123 辐射防护产业发展与江苏诚鑫的优势

Speaker: 史轶君（总经理） (宜兴市诚鑫辐射防护器材有限公司)

辐射防护产业发展与江苏诚鑫的优势.pdf

EW & tt: 2

Zoom Link, ID:85910938851, Code: 848529

124 Off-Z-pole data and New Physics

Speaker: Zhuoni Qian (Hangzhou Normal University)

202410_hz_cepc.pdf

125 Testing Resonance of Unstable Particles at Lepton Colliders

Although the future lepton colliers (including CEPC, FCC-ee, and ILC) are designed for the precision measurement of the Higgs boson properties, the Z-pole run can also serve as a Z factory with a large number of Z bosons to be produced. This provide new opportunities at the Z pole for both new physics search and even the precision measurement of the Standard Model processes. I would talk about two physics cases. One is using the asymmetric measurements around the Z pole to probe the dimension-6 operators and the other is using the lineshape to test the usual Brei-Wigner resonance assumption for an unstable intermediate particle. Both provides strong physics cases for the Z pole run at Higgs factories.

Speaker: Shao-Feng Ge (SJTU)

241024_CEPC.pdf

126 Probing Neutral Triple Gauge Couplings via Zgamma production at e+e- colliders

Speaker: Rui-Qing Xiao (SJTU)

NTGC-CEPC.pdf

127 Prospects for constraining light-quark electroweak couplings at Higgs factories

Electroweak Precision Measurements are stringent tests of the Standard Model and sensitive probes to New Physics. Accurate studies of the Z-boson couplings to the first-generation quarks could reveal potential discrepancies between the fundamental theory and experimental data. Future e+e- colliders offering high statistics of Z bosons would be an excellent tool to perform such a measurement based on comparison of radiative and non-radiative hadronic decays. Due to the difference in quark charge, the relative contribution of the events with final-state radiation (FSR) directly reflects the ratio of decays involving up- and down-type quarks. Such an analysis requires proper modeling and statistical discrimination between photons coming from different sources, including initial-state radiation (ISR), FSR, parton showers and hadronisation. In our contribution, we show how to extract the values of the Z couplings to light quarks and present the estimated uncertainties of the measurement.

Speaker: Krzysztof Mekala (University of Warsaw / DESY)

Light_quarks_Mekala_CEPC24.pdf

Silicon Detector: 1

Zoom Link, ID:81317080254, Code:103003

MAPS chip R&D at CCNU1.pptx

128 Introduction

Speakers: Christine HU-GUO (I) , Dr Xiangming Sun (CCNU) , 梁志均 LIANG Zhijun

129 4D tracking detector development in DRD3

Speaker: Dr Alessandro Tricoli

Tricoli_4Ddet_CEPCworkshop_Oct24.pdf

130 CEPC Time of Flight and outer tracking detector

Speaker: Yunyun Fan（樊云云） (IHEP)

20241024OTK_ToF_YYF-v3.pdf

131 LGAD sensor development ( From ATLAS high granularity timing detector to future timing detector)

Speaker: Mei Zhao (高能所, IHEP)

LGAD development v3_2024 CEPCWS_Mei.pdf

132 ACADIA development

Speaker: Manuel Dionisio Da Rocha Rolo (INFN Torino)

20241024_ARCADIA_CEPC.pdf

Accelerator: 4

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Convener: Wenhui Huang/Jiaru Shi

133 Accelerator activities in Thailand

Speaker: Sakhorn Rimjaem （remote）

134 CEPC accelerator instrumentation EDR plan and status

Speakers: Jun He (高能所) , Yanfeng Sui (高能所)

CEPC accelerator instrumentation EDR plan and status -20241024V3.pptx

135 CEPC control system

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

CEPC control system.pptx

136 CEPC MDI Cryomodule design status

Speaker: ZHANG Xiangzhen (高能所)

CEPC MDI Cryomodule design status.pptx

137 CEPC Interaction Region engineering design status

Speaker: Haijing Wang (高能所)

CEPC Interaction Region engineering design status.pptx

EW & tt: 3

Zoom Link, ID:85910938851, Code: 848529

138 Impact of parity violation on quantum entanglement and Bell nonlocality

Speaker: Yong Du (TD Lee Institute)

CEPC2024-YongDu.pdf

139 Testing Bell inequalities and probing quantum entanglement at CEPC

The (Circular Electron Positron Collider) CEPC is proposed in China, which is one of the most attractive future colliders. It’s also an ideal platform to search for new physics, test the standard model, and research a set of advanced focus in physics as a future Higgs factory. To test Bell inequalities, we construct observable for the H → ZZ∗ process in CEPC through the use of (Collins-Gisin-Linden-Massar-Popescu) CGLMP inequality, which can derive its value from the density matrix of Z boson pairs from di-boson Higgs decay. With the application of Monte Carlo simulations, we study the observable $I_{3}$ of the CGLMP inequality for our signal processes, which provides reliable evidence of Bell inequalities violations. In this study, we investigate and simulate the possible backgrounds on CEPC at a collision energy of 250 GeV.

Speaker: Ruobing JIANG

CEPC_Ruobing.pdf

140 Quantum tops at circular lepton colliders

Speaker: Simone Tentori (UCLouvain)

QuantumTopsCEPC_Tentori.pdf

141 EW corrections at future colliders

Speaker: Davide Pagani (INFN, Bologna)

EW-FC.pdf

142 Top Quark EW Coupling Precision Measurement At CEPC

Our research focuses on investigating the electroweak couplings of the top quark at the Circular Electron Positron Collider (CEPC) for semileptonic top pair production at a center-of-mass energy of 360 GeV. This energy is close to twice the top quark mass, which enhances the measurement precision of the top quark mass. This study utilizes both CEPC-Full and CEPC-Fast simulations.
The CEPC provides an ideal environment for measuring these couplings, and it is expected to yield higher precision measurements than those achieved at the Large Hadron Collider (LHC). The data were generated and passed through CEPC-Soft reconstruction and simulations softwares.
Our findings indicate that the top quark mass can be reconstructed, resulting in a value of 172 GeV with a reasonable standard deviation, without including systematic uncertainties. Additionally, we conducted a background study that achieved high suppression rates, nearly eliminating other Standard Model backgrounds.
The measurement of forward-backward asymmetry will enable us to extract the photon and Z0 couplings of the top quark, which can be analyzed through the angle of the decay lepton in the semileptonic decays of the top pair in the top quark's rest frame.

Speaker: MUSTAPHA BIYABI (高能所)

CEPC_WS_2024.pdf

Silicon Detector: 2

Zoom Link, ID:81317080254, Code:103003

MAPS chip R&D at CCNU1.pptx

143 CEPC Inner Silicon Tracker towards Ref-TDR

Speaker: Yiming 一鸣 Li 李 (IHEP)

20241024_CEPC_SiITK_v2.pdf

144 CMOS Strip Chip Design for CEPC ITK

Speaker: Xin Shi (IHEP)

CEPC_CMOS_Chip_Design_v4.pdf

145 HVCMOS based silicon tracking detector R & D

Speaker: Yanyan Gao (University of Edinburgh)

large_area_tracker_CEPC2024.pdf

146 MPD ITS Status and Perspectives

Speaker: Dr Yuri Murin (JINR)

Hangzhou_MPD-ITS.pdf

147 NICA tracker electronics R & D

Speaker: Dr XiangMing Sun (CCNU)

TDAQ: 1

Zoom Link, ID:87170162344, Code:625716

Conveners: Hongyu ZHANG (EPC, IHEP, CAS, China) , Kai Chen (Central China Normal University)

148 CEPC trigger simulation study

The Circular Electron-Positron Collider (CEPC) is a next-generation particle collider designed for precision measurements and searches for new physics. An essential component of this experiment is the trigger system, which will select important events from the vast amount of data. This presentation shows the study of the CEPC trigger system. We will discuss some algorithms used in trigger processes, including the possibility of using neural network to enhance trigger efficiency, and the preliminary result for the simulations.

Speaker: Boping Chen

CEPCworkshop2024.pdf

149 Allen design and development for HLT1 at LHCb

Speaker: Peilian Li (UCAS)

LHCbAllen_CEPCworkshop_PeilianLi.pdf

150 FPGA acceleration for Hlt1 at LHCb

Speaker: Ao Xu (Peking University)

axu_cepc2024.pdf

151 DAQ System Development for CEPC

This report introduces the research and achievements made in developing the DAQ system aimed at CEPC.
First, the work on the data flow framework RADAR will be presented. RADAR is a streaming readout framework developed in-house. Its early version has been operating stably in the LHAASO (Large High Altitude Air Shower Observatory) experiment, and the current version is set to be deployed for the JUNO (Jiangmen Underground Neutrino Observatory) experiment. The current upgrades and next development goals are aimed at CEPC, with the objective of providing a higher performance, more reliable, and flexible data acquisition framework. Additionally, exploration of heterogeneous acceleration methods is underway to leverage the unique features of different hardware platforms to enhance online data processing capabilities.
To better support the operation of the data flow software, online service software has also been developed. This software manages the data flow software and provides a rich set of system interfaces and services, enhancing the stability and reliability of the system. It also offers interfaces for DAQ users, presenting comprehensive system status through extensive information monitoring and intuitive visualization. Furthermore, a machine learning-based histogram anomaly diagnosis method has been introduced to reduce user burden and improve the accuracy and real-time detection of anomalies.
Finally, an LLM-based (Large Language Model) operational assistant is being developed with the objective of providing private information queries, automated operational monitoring and alerts, and intelligent anomaly analysis. The objective is to enhance the efficiency of the data acquisition system's operational information collection, extraction, and processing, thereby ensuring optimal and reliable functionality.

Speaker: 筱璐 季 (高能所)

DAQ System Development for CEPC.pdf

15:30 Coffee break

Accelerator: 6

Zoom Link, ID:84479508720, Code:925544

Convener: Philip Burrows （remote） (John Adams Institute, Oxford University)

152 IJClab accelerator activities

Speaker: Angeles Faus-Golfe

EAJADE_WP1_secondments_2024.pptx

153 Positron source and capture system (HTS-solenoid)

Speakers: Dr Fahad ALHARTHI （remote）, Iryna Chaikovska

Falharthi_FCC-ee_PS_CEPC2024.pdf

154 FCC-ee collimation

Speaker: Giacomo Broggi (Remote)

155 On high gradient accelerator technology development in Tsinghua University

Speaker: Jiaru Shi

CEPC-2024_Tsinghua_High-gradient.pdf

156 CEPC dumps and the dump experimental hall

Speaker: Zhongjian Ma (高能所)

CEPC dumps and the dump experimental hall-mazhj-20241024.pdf

CEPC dumps and the dump experimental hall-mazhj-20241024.pptx

157 Radiation in the tunnel and its mitigation for CEPC EDR

Speaker: Guangyi Tang (IHEP)

CEPC workshop2024 RP.pptx

Higgs: 1

Zoom Link, ID:85910938851, Code: 848529

158 Measurements of decay branching fractions of the Higgs boson to hadronic final states at the CEPC

Speaker: Xiaotian Ma (高能所)

maxiaotian_20241024.pdf

159 Update on the SM Higgs precision measurements at CEPC

Speaker: Kaili Zhang (IHEP)

20241024_CEPCHiggs_v2_Kaili.pdf

160 A triple Z' signal via light Higgs interaction in Z-factories

Speaker: Takaaki Nomura (Sichuan University)

Nomura1024.pdf

161 The 95 GeV Higgs boson at CEPC

Speaker: Sven Heinemeyer (IFT (CSIC))

sven.pdf

Silicon Detector: 3

Zoom Link, ID:81317080254, Code:103003

MAPS chip R&D at CCNU1.pptx

162 MAPS development in DRD3

Speaker: Dr Eva Vilella (The University of Liverpool)

20241024_DRD3_monolithic_CMOS.pdf

163 CEPC vertex detector development

Speaker: Ying ZHANG (IHEP)

CEPC-vertex_20241024_upload.pdf

164 BELLE2 vertex detector

Speaker: Dr Jérôme BAUDOT

belle2vtx-baudot-cepc2024.pdf

165 ALICE ITS3 vertex detector upgrade

Speaker: Dr Corrado .Gargiulo

CEPC2024_ALICE_ITS3_mechanics_cooling.pdf

TDAQ: 2

Zoom Link, ID:87170162344, Code:625716

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

166 Introduction on ATLAS Phase-II Global Trigger and GCM design

Speaker: Dr Weiming Qian (STFC Rutherford Appleton Laboratory)

IntroductionATLASGlobalTrigger.pdf

167 FELIX Readout System

Speaker: Prof. Mengqing Wu (Radboud University Nijmegen and Nikhef)

CEPC-FELIX_MW.pdf

168 Hardware trigger design for CEPC ref-TDR

CEPC a large international scientific facility proposed by the Chinese particle physics community to explore the aforementioned physics program. It is designed to operate at around 91.2 GeV with 23ns beam spacing as a Z factory, at around 160 GeV with 257ns beam spacing of the W W production threshold, and at 240 GeV with 591ns beam spacing as a Higgs factory.Trigger system with the function of rough selection of the relevant objects (jet, e, muon, tau,v, ...) and combinations, is a critical system that determines the quality of the data taking. This report will introduce the preliminary design scheme of the CEPC trigger system and design scale based on current research.

Speaker: Jingzhou ZHAO (高能所)

CEPC workshop 2024-hangzhou_v2.pdf

169 Versal FPGA based development for HEP

Speaker: Yun-Tsung Lai (KEK IPNS)

20241024_Versal.pdf

17:35 Discussion

Plenary: Public Lecture at ZJU; Organized bus transportation

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170 李政道先生与中国高能物理的发展

Speaker: Yifang Wang (高能所)

171 物质最深处

Speaker: 原宁 高 (北京大学)

Friday, 25 October

Accelerator: 7

Zoom Link, ID:84479508720, Code:925544

Convener: Jie GAO (IHEP)

172 CEPC polarization study

Speaker: Zhe DUAN (高能所)

CEPC_polarization_study_progress.pptx

173 Plasma based wakefield acceleration and its applications

Speaker: Wei Lu (Tsinghua University)

CEPC-2024-weilu.pptx

174 On capture and aceleration of slow muon (from MeV to GeV) beam by wake field from PKU

Speakers: Xueqing Yan (P) , Xuezhi Wu

20241025-cepc-wuxuezhi-YXQ-EZ.pptx

175 IHEP plasma accelerator study status

Speaker: Dazhang LI (IHEP)

20241025-PBA@IHEP-LIDZ.pdf

176 Study of channel radius in beam driven plasma wakfield

Speaker: Ming Zeng

2024cepc_MingZeng.pdf

Gaseous Detector: I

Zoom Link, ID:81317080254, Code:103003

177 Progress of CEPC TPC Towards the TDR

The Circular Electron Positron Collider accelerator Technical Design Report (TDR), as a Higgs and high luminosity Z factory, has been released in 2023. The baseline design of a detector concept consists of a large 3D tracking system, which is a high precision (about 100$\mu$m) spatial resolution Time Projection Chamber (TPC) detector as the main track embedded in a 3.0T solenoid field, especially for the accelerator operating at Tera-Z. TPC requires the longitudinal time resolution (<100ns) and the physics goals require PID resolution (<3%).

In this talk, we will present the feasibility and progress of the high precision TPC technology for CEPC, even at Tera-Z. The fundamental parameters such as the spatial resolution, PID with the good separation power and the drift velocity were studied by the simulation and measurement using a TPC prototype with 500mm drift length. We will review the track reconstruction performance results and summarize the updated R&D towards TPC construction for CEPC physics and detector TDR.

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

CEPC_TPC_Workshop_Huirong_20241025.pdf

178 Status of CEPC DC

Speaker: Mingyi Dong (IHEP)

Status of drift chamber for CEPC.pdf

179 Large Area GEM Production at Peking University

GEM-based detectors are widely used in High Energy Physics environments due to their good rate capability and inherent resistance to classical aging. Consequently, GEM detectors are particularly advantageous for high-rate environments. In the past decade, the Peking University (PKU) group has established a local lab for large area GEM detectors and electronic boards. The related R&D and production activities are conducted under the RD51 collaboration and the CMS phase-II upgrade projects. This talk will give a brief review of these activities at the PKU lab and an outlook of prospects for detectors at the future high energy circular electron positron collider.

Speaker: Dayong Wang (Peking University)

20241025_CEPC2024_PKUGEM.pdf

180 TMM: Triple Micro-Mesh gaseous structure with ultralow ion backflow for gaseous photon detectors

Gas photomultiplier tubes (gas-PMT) for visible light detection using micro-pattern gas detectors have been widely studied owing to their potential advantages, such as large detection area with low cost, high spatial and time resolutions, and resistance to magnetic field. But photocathodes sensitive to visible light exhibit a significant aging effect when subjected to excessive ions bombardment. Approximately 20% degradation of quantum efficiency was reported even for low accumulated charge of 0.4 μC/mm^2 on the bialkali photocathode. Therefore, very low ion-backflow (IBF) is crucial to visible light-sensitive gas-PMTs, and both high gas gain and photoelectron collecting efficiency are required for single photon detection. we have previously reported the design, fabrication and optimization of a double micro-mesh gaseous structure (DMM). An IBF ratio as low as 3 × 10^(-4) was obtained with a DMM detector prototype. In this detector, the most backflow ions come from the secondary gas amplification stage of the DMM. Thus, a triple micro-mesh gaseous structure (TMM) becomes a natural extension of the DMM to further suppress the IBF. In this report, we present the design and fabrication of the TMM based on the DMM experience. Multiple TMM prototypes were built and characterized with X-rays and UV light. A gas gain over 4 × 10^4 and an IBF ratio of lower than 3 × 10^(-5) were achieved in the X-ray test. The achieved IBF of the TMM is one order of magnitude better than that of the DMM. Furthermore, a very high gain with ultra-low IBF ratio for single electrons was obtained with the TMM using UV light. The energy resolution of the TMM for X-rays was optimized by enhancing electron collecting efficiency. The demonstrated performance of the TMM shows that it is a very promising technology for electron amplification for visible-light gas-PMTs. The developing progress of Gas-PMT based on TMM is also reported.

Speaker: Kunyu Liang (中国科学技术大学近代物理系)

TMM-CEPC2024-v1.pptx

181 Simulation and prototyping of Pixelated readout TPC for CEPC

Speaker: Xin She (IHEP,CAS)

CEPC2024_Hangzhou_shexin_v04.pdf

Higgs

Zoom Link, ID:85910938851, Code: 848529

182 Exploring the BSM Potential of Anomalous Neutral Gauge Couplings and Electroweak Phase Transition with CEPC Detector Simulation

https://arxiv.org/abs/2404.15937
Front. Phys. 20(1), 015201 (2025) [doi:10.15302/frontphys.2025.015201] (Cover Story Highlight)

Neutral triple gauge couplings (nTGCs) are absent in the Standard Model (SM) and at the dimension-6 level in the Standard Model Effective Field Theory (SMEFT), arising first from dimension-8 operators. As such, they provide a unique window for probing new physics beyond the SM. These dimension-8 operators can be mapped to nTGC form factors whose structure is consistent with the spontaneously-broken electroweak gauge symmetry of the SM. In this work, we study the probes of nTGCs in the reaction $e^{+}e^{−}$→Zγ with Z→$ℓ{+}ℓ^{−}$(ℓ = e,μ) at an $e^{+}e^{−}$ collider. We perform a detector-level simulation and analysis of this reaction at the Circular Electron Positron Collider (CEPC) with collision energy $\sqrt{s}$ = 240 GeV and an integrated luminosity of 5 ab$^{−1}$. We present the sensitivity limits on probing the new physics scales of dimension-8 nTGC operators via measurements of the corresponding nTGC form factors.

https://arxiv.org/abs/2203.10184
LHEP 2023 (2023) 436 [doi:10.31526/lhep.2023.436]

A strong first-order electroweak phase transition (EWPT) can be induced by light new physics weakly coupled to the Higgs. This study focuses on a scenario in which the first-order EWPT is driven by a light scalar s with a mass between 15-60 GeV. A search for exotic decays of the Higgs boson into a pair of spin-zero particles, h→ss, where the s-boson decays into b-quarks promptly is presented. The search is performed in events where the Higgs boson is produced in association with a Z boson, giving rise to a signature of two charged leptons (electrons or muons) and multiple jets from b-quark decays. The analysis is considering a scenario of analysing 5000 $fb^{−1}$ $e^{+}e^{−}$ collision data at $\sqrt{s}$ = 240 GeV from the Circular Electron Positron Collider (CEPC). This study with 4b final state conclusively tests the expected sensitivity of probing the light scalars in the CEPC experiment. The sensitivity reach is significantly larger than that can be achieved at the LHC.

Speakers: Danning Liu, Shu Li (TDLI, SJTU) , Xuliang Zhu (Shanghai Jiao Tong University) , Zhen Wang

CEPC-exoH-nTGC.pdf

183 (Online)Testing the Electroweak Phase transition and Dark Matter Phenomenology at the LHC - Implications for the CEPC

Speaker: Wenxing Zhang

184 Current status of 2HDMs for muon g-2

Speakers: MICHIHISA TAKEUCHI (Sun Yat-sen University) , Michihisa TAKEUCHI (Kavli IPMU Tokyo)

20241025_CEPC_Hangzhou.pdf

185 Accidental Suppression of Wilson Coefficients in Higgs Couplings

Speaker: Zhen Liu (University of Minnesota)

2_HiggsSuppression_CEPC2024_BSM_ZhenLiu_Oct.pdf

MDI and Mechanical: 1

Zoom Link, ID:87170162344, Code:625716

Convener: Haoyu SHI (IHEP)

186 QCS on SuperKEKB/BelleII

187 Progress of CEPC detector magnet toward Ref-TDR

Speaker: Feipeng NING (IHEP)

CEPC detector magnet - hangzhou.pptx

188 Physical design of CEPC detector magnet

Speaker: UNKNOWN 王梦琳

Physical design of CEPC detector magnet.pptx

189 CEPC Detector Integration

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

20241025CEPC Detector Mechanical Integration.pptx

10:30 Coffee break

Accelerator: 8

Zoom Link, ID:84479508720, Code:925544

Convener: Xueqing Yan (PKU)

190 CEPC machine protection and transport line systems

Speaker: Xiaohao Cui (Accelerator Center)

CEPC machine protection and transport line systems.pptx

191 CEPC RF power sources and power distribution EDR plan and status

Speaker: Zusheng Zhou (IHEP)

CEPC RF power sources and power distribution EDR plan and status.pdf

192 CEPC Mechanical system EDR plan and status

Speaker: Haijing Wang (高能所)

CEPC mechanicss system EDR plan and status.pptx

193 CEPC alignment and installation EDR plan and status

Speaker: Xiaolong Wang (高能所)

CEPC alignment and installation EDR plan and status-V2.pptx

194 CEPC engineering design considerations

Speaker: Hongying Zou (黄河勘测规划设计研究院有限公司)

Flavor: 1

Zoom Link, ID:85910938851, Code: 848529

Convener: Changzheng YUAN (IHEP, Beijing)

195 Vcb measurement in W decays (online)

Speaker: Lingfeng Li (HKUST)

196 LFV at future e+e- colliders (online)

Speaker: Dr Pankaj Munbodh

197 Hadron spectroscopy from LHCb

Speaker: Liming Zhang (Tsinghua University)

Liming-LHCb-CEPC-v2.pdf

198 Charmoniumlike states at BESIII

Speaker: Yuping GUO (Fudan University)

GuoYP-20241025-CEPC.pdf

Gaseous Detector: II

Zoom Link, ID:81317080254, Code:103003

199 Gas Deterctors and Electronics at CIAE

Speaker: Xiaomei Li (China Institute of Atomic Energy)

200 Needed R&D for running a TPC at a circular collider

Speakers: Paul Colas (CEA/Irfu U. Paris Saclay) , Paul Colas (CEA/Irfu Saclay)

20241025-HangzhouTPC.pptx

201 Update of the IDEA drift chamber

Speaker: Paolo Giacomelli (INFN-Bo)

IDEA-drift-chamber-CEPC-workshop-2024.pdf

IDEA-drift-chamber-CEPC-workshop-2024.pptx

202 Ion feedback suppressing using graphene membrane

Speaker: Kang Jia

SDU_Graphne_CEPCWS202410.pdf

203 GridPix readout TPC R&D

Speaker: Peter Kluit (Nikhef)

GridPix_TPC_R&D.pdf

International Industrial Connection: 1

Zoom Link, ID:87170162344, Code:625716

204 SiPM readout ASIC from Microparity

Microparity is a microelectronic company with speciality in single photon detection based in Hangzhou, China. The product spectrum of Microparity spans over different kinds of single photon detectors, e.g. SiPMs and SPADs, as well as their readout ICs, e.g. high resolution TDCs, low noise readout ICs for large dynamic SiPMs , Time of Flight Position Emission Tomography, distance ranging using FSI and BSI SPAD arrays etc. The application fields of the single photon detection products focus mainly on consumer, medical and automobil electronics. A few photon detection chips related to collision/detector physics will be presented.

Speaker: Wei Shen (Microparity (杭州宇称电子))

Microparity single photon product introduction.pdf

205 Research and application progress of cadmium zinc telluride (CZT) semiconductor radiation detectors

Imdetek Co. Ltd.

Speaker: Mr Shouzhi Xi (Imdetek Co. Ltd.)

206 High Energy Physics and Medical Imaging (United-Imaging)

Shanghai United Imaging Healthcare Advanced Technology Research Institute Co., Ltd

Speaker: Mr Pengwei Xie (Shanghai United Imaging Healthcare Advanced Technology Research Institute Co., Ltd)

207 Manufacturing and assembly processes of TSV (Through-Silicon Via) and sensor applications

from NCAP
TSV 制造与组装工艺及传感器应用（华进半导体）

Speaker: Mr Zhengyu Ren (NCAP)

TSV制造与组装工艺及其应用.pdf

208 New Generation Software-defined Modular Instrument Platform

EVERACQ technologies company has expanded its modular design approach to the fields of FPGA development, drivers and software design, introducing a new generation of software-defined modular instrument platform—the μXI(micro eXtensions for Instrumentation) platform. The platform features a logic reconfigurable synchronous timing controller which integrates CPU and FPGA. By implementing triggering and synchronous timing technologies on FPGA chips, the controller achieves distributed high-precision time synchronization, enabling sub-nanosecond level precise clock synchronization across long-distance modules. The platform incorporates an IPMI intelligent management system, which enhances system reliability through intelligent monitoring. Moreover, the robustness, modularity, and Eurocard mechanical packaging characteristics of the chassis meet the mechanical and electrical specifications required for testing, measurement, and data acquisition applications. This platform technology can be applied in the fields of test and measurement, instrumentation, and industrial control

Speaker: Yiqing奕菁 Cao曹

新一代模块化仪器平台20241025.pptx

209 Design and Development of Thin-Walled Vacuum Chambers and High-Pressure Chambers for Applications in Physics Experiments

应用于物理实验的薄壁真空室和高气压室设计研制

Speaker: Yuntao Zhao (Shenyang YiLian Vacuum Technology Co. Ltd)

ShenyangYilian_rev.pdf

Flavor: 2

Zoom Link, ID:85910938851, Code: 848529

Convener: Kai Yi (Nanjing Normal University)

210 White Paper on Flavour at the CEPC: status report

Speaker: Manqi Ruan (IHEP)

CEPC Flavor Physics WP-v2.pdf

211 Prospect for measurement of the CP-violating phase $\phi_s$ in the $B_s\rightarrow J/\psi \phi$ channel at a future $Z$ factory

The CP-violating phase $\phi_s$, the $B_s$ decay width ($\Gamma_s$), and the $B_s$ decay width difference ($\Delta\Gamma_s$) are sensitive probes to new physics and can constrain the heavy quark expansion theory. The potential for the measurement at future $Z$ factories is studied in this manuscript. It is found that operating at Tera-$Z$ mode, the expected precision can reach: $\sigma(\phi_s) = 4.6~\mathrm{mrad}$, $\sigma(\Delta\Gamma_s) = 2.4~\mathrm{ns^{-1}}$ and $\sigma(\Gamma_s) = 0.72~\mathrm{ns^{-1}}$. The precision of $\phi_s$ is 40\% larger than the expected precision with the LHCb experiment at HL-LHC. If operating at 10-Tera-$Z$ mode, the precision of $\phi_s$ can be measured at 45\% of the precision obtained from the LHCb experiment at HL-LHC. However, the measurement of $\Gamma_s$ and $\Delta\Gamma_s$ cannot benefit from the excellent time resolution and tagging power of the future $Z$-factories. Only operating at 10-Tera-$Z$ mode can the $\Gamma_s$ and $\Delta\Gamma_s$ reach an 18\% larger precision than the precision expected to be obtained from LHCb at HL-LHC. The control of penguin contamination at the future $Z$-factories is also discussed.

Speaker: Mingrui Zhao (China Institute of Atomic Energy)

slides_CEPCworkshop.pdf

212 CMS top decays and spin correlations

Speaker: Kai-Feng Chen (National Taiwan University)

cepc-workshop-2024.pdf

International Industrial Connection: 2

Zoom Link, ID:87170162344, Code:625716

213 Phyclover-20 years in the service of physics

Speaker: Mr Tao Cen (Phyclover)

CEPC_polyclover.pptx

214 Intelligent special power supply service provider from Fullde Electronics

Fullde Electronics Co., Ltd. is a manufacturer focusing on the development and production of high-reliability power supplies, the company is committed to the development of high- and low-voltage DC separated, chassis plug-in power supplies, energy storage, UPS power supplies and other special power supplies. Now the power supply products have been served in the European Organization for Nuclear Research (CERN) HGTD project, China’s “artificial sun” (EAST) project, the Jiangmen Neutrino Experiment, Spallation Neutron Source, LHAASO and other large scientific facilities. Among them, the maximum voltage of high-voltage chassis can meet the demand of plus or minus 5000V5mA, ripple voltage 5mVpp, current monitoring resolution is less than 10nA, low-voltage chassis can realize 85% high efficiency under the premise of ripple voltage 5mVpp, high-voltage power supply and low-voltage power supply are supported by OPC-UA, EPCIS and other kinds of communication protocols, single-channel can be independently controlled and protected.
At present, our high voltage power supply has provided 2500 channels in LHAASO and is expected to provide 500 channels per year in the future operation and maintenance; 200 channels in CERN and has been running stably for 2 years, and is expected to provide 9000 channels of high voltage in the next year; and 2000 channels of low voltage power supply in the Spallation Neutron Source and has been running stably for 3 years; the UPS power supply provided by the Jiangmen Neutrino Experiment, as well as the low-voltage power supply for electronics, has been in continuous and stable operation for 2 years.
High reliability as an important requirement for power supplies for large scientific facilities. In recent years, our company has done a lot of targeted research on the reliability and stability of power supplies in harsh environments such as high altitude, thunderstorms, high humidity and strong electromagnetic interference, and finally has successfully passed the tests of these complex environments. At the same time, in order to meet the new demands for large scientific facilities in the future, our power supply products are committed to the high power density under the premise of low-temperature wave, high reliability under the premise of intelligent, and anti-irradiation direction to continue to serve the construction of high-energy physics devices.

Speaker: Yongqian永乾 Lai来

湖南福德电气有限公司2024.10.9.pptx

215 Semiconductors & IC Design and Test Overview

from Keysight Technologies

Speaker: HaiChuang海川 Yang杨 (Keysight)

01 Semiconductors_ICs Design and Test Overview-20241025.pdf

216 Phase Noise and its Measurements

from Keysight Technologies

Speaker: HaiChuan海川 Yang杨 (keysight)

02 Phase Noise and its Measurement Solutions-20241025.pdf

217 The Next Generation NAT-MCH

After almost 18 years of successful deployments, the 3rd generation of NAT-MCH is getting closer to its end of life, while the 4th generation of NAT-MCH is available now.

The 4th generation is MTCA.0 Rev 3 compliant and has been designed to meet the upcoming requirements addressed by the next generation of MicroTCA as close as possible already.

It provides a lot of improvements and new features and functions, such as 10GbE base switch with 25GbE uplinks, new 40/100GbE fat pipe hub with 10/40/100GbE uplinks, new PCIe Gen 4 fat hub, new CLK module with replacement for IDT multiplexer, new web and harmonized CLI interface in order to name a few.

After a short introduction to new features and how new and existing customers can benefit from these, N.A.T will explain how existing customers for the 3rd generation of NAT-MCH can easily migrate to the 4th generation MCH in existing applications.

Speaker: Heiko Koerte (N.A.T. GmbH)

IHEP NAT-MCH-Gen4.pdf

218 How to improve accuracy of measurement when using an oscilloscope

from LeCroy

Speaker: Mr Xinyi Jiang

CEPC-LECROY20241024.pdf

MDI + Accelerator: 2

Zoom Link, ID:84479508720, Code:925544

Convener: 雷(Lei) 张(Zhang) (南京大学(Nanjing University))

219 Metrology challenges in integrated luminosity measurement at CEPC and ILC

Speaker: Ivan Smiljanić (Vinca Institute of Nuclear Sciences)

CEPC_ILC_metrology_challenges.pdf

220 Measuring QED to 10^-4 with radiative Bhabha for e+e- collision luminosity

Speaker: Suen Hou (IPAS)

20241025_HangZhou-lumical-v4b.pdf

221 CEPC LumiCal Design Status

Speaker: 行阳 孙 (Nanjing University)

LumiCal.pptx

222 Mechanical Design of the Beampipe and LumiCal

Speaker: 龙岩 何 (高能所)

Mechanical Design of the Beampipe and Lumical(2).pptx

Mechanical Design of the Beampipe and Lumical.pptx

Mechanical Design of the Beampipe and Lumical.pptx

223 CEPC Fast Luminosity Detector design using SiC

Speaker: 希媛 张

CEPC Fast luminosity detector design using SiC-XYZ.pdf

PID& Misc: 1

Zoom Link, ID:81317080254, Code:103003

Convener: XiaoLong Wang (Fudan University)

224 PID at LHCb experiment

Speaker: Sajan Easo (STFC)

PID-LHCb-AT-CEPC-Oct25-2024.pdf

PID-LHCb-AT-CEPC-Oct25-2024.pptx

225 Aerogel based Cherenkov counters for momenta above 20 GeV/c

Silica based aerogel is unique transparent material with tuneable refractive indexes between gaseous and liquid substances. Since 1986 a huge experience in aerogel production for HEP experiments was accumulated in Novosibirsk by Budker Institute of Nuclear Physics in cooperation with Boreskov Institute of Catalysis. Refractive indexes of aerogels produced in Novosibirsk are in range from 1.008 to 1.13. Rayleigh light scattering length at wavelength 400nm for synthesised aerogels usually is above 40mm. Recent progress and current status of aerogel based Cherenkov detectors development in Novosibirsk are presented. Several concepts of RICH detectors based on aerogels with refractive index around n=1.008 are considered. Results of GEANT4 simulation are presented. Requirements to position-sensitive photon detectors are formulated, some technical solutions and availabilities are discussed. Conceptual design of RICH detector prototype based on aerogels with n=1.008 and beam tests plan are given as well.

Speaker: Alexander Barnyakov (Budker Institute of Nuclear Physics)

AerogelPIDforCEPC_WS2024.pdf

226 Physics impact from PID

Speaker: Manqi Ruan (IHEP)

Pid requirement at CEPC.pdf

15:30 Coffee break

Flavor: 3

Zoom Link, ID:85910938851, Code: 848529

Convener: Ulrik Egede (Monash University)

227 Flavour-violating Higgs decays

Speaker: Dr Michele Tammaro

CEPC24_Tammaro.pdf

228 Polarised Lambda_B samples

Speaker: Dr Michal Kreps

CEPC2024.pdf

229 (g-2)_tau at CMS

Speaker: Dayong Wang (Peking University)

20241025_CEPC2024_CMStaug-2.pdf

230 tau physics at Belle II

Speaker: Wenzhe Li (Beihang University)

Tau physics at Belle II.pdf

231 Decays involving taus at LHCb

Speaker: Bo Fang (University of Chinese Academy of Sciences)

TauAtLHCb_Hangzhou_bfang_241025.pdf

Joint SiDet + Electronics

Zoom Link, ID:87170162344, Code:625716

232 ALICE ITS3 MAPS sensor development

Speaker: Dr Alexander Kluge

CEPCWorkshop.102024.PVL.pptx

233 Power distribution over the wafer-scale monolithic pixel detector

Speaker: Szymon Bugiel

2024_MOSAIX_powering.pdf

234 HVCMOS Pixels R&D for CEPC ITK

Speaker: Yang ZHOU (IHEP)

HVCMOS_CEPC_hangzhou.pdf

235 4D Hybrid R & D presentation and discussion

Speaker: Dr Mitch Newcomer (University of Pennsylvania)

Hybrid 4D Collaborations.pdf

MDI + Accelerator: 3

Zoom Link, ID:84479508720, Code:925544

Convener: Suen Hou (IPAS)

236 SuperKEKB/BelleII MDI Status

Speaker: Tak Shun LAU (KEK)

20241025_MDI_CEPC2024_TSLau.pdf

237 FCC-ee MDI Status

Speaker: Andrea Ciarma (Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Frascati)

2024-10-25_CEPCWS_FCCeeMDI_CIARMA.pdf

238 Beamstrahlung backgrounds in ILD at ILC and FCCee

Speaker: Daniel Jeans (KEK)

TPC-BG-CEPC2024.pdf

239 Study Status on Beam Backgrounds and MDI at the CEPC

Speaker: Haoyu SHI (IHEP)

Shy_CEPCHZ2024_20241025.pdf

240 Background analysis of CEPC vertex detector

Speaker: Hancen LU (鲁函岑) (IHEP)

VXDBKGAnly_talk_CEPCWS.pdf

241 Analysis of the beam background for TPC at the high luminosity Z pole on CEPC

Speaker: Jinxian Zhang

Analysis of the beam background for TPC at the high luminosity Z pole on CEPC.pdf

PID& Misc: 2

Zoom Link, ID:81317080254, Code:103003

Convener: Sajan Easo (STFC)

242 MTD based on LYSO and SiPM at CMS experiment

Speakers: Jin Wang (school of physics Peking Uniersity) , Xiaohu Sun (Peking University)

MTD_BTL_Jin_CEPC_20241025.pdf

243 RPC at colliders – from LHC to CEPC

Speaker: Jun Guo (S)

CEPC_conference_20241025.pdf

244 The development of radiation-resistant SiPM at IHEP and SPD with SiPM

Speaker: Tianyuan Zhang

CEPC2024withSPD.pdf

245 PID Performance of CEPC ToF and Outer Tracker

In order to fulfill the requirements for precision physics analysis in CEPC, good particle identification and trajectory measurements are essential. In the CEPC preTDR detector, a dedicated tracking system, including Vertex Detector, Silicon Inner Tracker, Time Projection Chamber, and Time of Flight (ToF) Outer Tracker, is proposed to perform excellent track position, momentum, and flighting time measurements. The ToF Outer Tracker is designed to achieve a few tens picoseconds timing resolution for tracks which could benefit the particle identification (PID) of the CEPC. Besides, due to a novel silicon timing sensor called AC-LGAD will be used for the Outer Tracker, the ToF Outer Tracker could also perform a few micrometer position resolution measurements for tracking hits. This information can be used to improve the momentum resolution for high momentum tracks. This talk will present the performance of the ToF Outer tracker with the simulated data from the CEPCSW. The performance study includes two parts: the impact on PID and the effect on tracking momentum measurement. Based on that, this talk will also show the physics potential for some benchmark physics channels with such a good ToF Outer Tracker performance.

Speaker: Yunyun Fan (IHEP)

20241025PID_OTK_ToF_YYF-v4.pdf

246 Pixelated readout gas detector for PID

Future circular electron-positron collider has been proposed as both Higgs factories and high-luminosity Z factories. The conceptual design of the updated detector includes a tracking system, with the Time Projection Chamber (TPC) serving as the primary tracking detector. The TPC offers high spatial resolution (approximately 100 µm over the entire drift length in a 3T magnetic field) in a large 3D volume, which is particularly important for operations at the high-luminosity Z pole (Tera-Z at a 2T magnetic field).

In this talk, we will present the feasibility and current status of using a high-precision TPC as the main tracking detector for electron-positron colliders. The TPC is designed to achieve good separation power, utilizing cluster counting, and we will discuss simulation results for both pad and pixelated TPC technologies for electron-positron colliders. Compared to pad readout in simulations, the high-granularity readout option for the TPC demonstrates better spatial resolution for single electrons, very high detection efficiency, excellent tracking, and superior PID performance (with a resolution of less than 3$\sigma$).

We will present the results of track reconstruction performance and dE/dx measurements, review the overall track reconstruction performance, and summarize the next steps toward TPC construction for CEPC physics and the detector Technical Design Report (TDR).

Speaker: Yue Chang (Nankai University)

CEPCWorkShop2024_V2.pdf

247 R&D status of the muon detector for CEPC

Speaker: Xiyang Wang (Fudan University)

R&D status of the muon detector for CEPC.pdf

18:30 Banquet

Saturday, 26 October

Accelerator: 9

Zoom Link, ID:84479508720, Code:925544

Convener: Garam Hahn

248 Online bunch-by-bunch bunch-length monitoring using synchrotron radiation

Speaker: Ji-gwang HWANG（remote）

CEPC_presentation.pdf

249 Low-Q cavity BPM with an ultra-high position resolution

Speaker: Siwon JANG

Low-Q cavity BPM with an ultra-high position resolution.pdf

250 CEPC sustainable development issues

Speaker: Yuhui Li

Efforts to make CEPC a green machine.pptx

251 CEPC green energy technologies

Speaker: Jinshu Huang

CEPC green energy technologies.pptx

252 CEPC DeepC Status

Speaker: Song Jin (IHEP，CAS)

CEPC DeepC status CEPC2024 v2.pdf

Electronics: 1

Zoom Link, ID:81317080254, Code:103003

Convener: Frank (Preferred name Mitch) Newcomer (University of Pennsylvania)

253 CEPC detector readout electronics, an overview

Speaker: Wei WEI (高能所)

CEPC_Elec_Overview.pdf

254 A timing circuit prototype design for sub-10ps time measurement applications

Speaker: Xiaoting Li (高能所)

CEPC2024report_cywang.pdf

255 A 14bit 100 MS/s Two-Step Split SAR ADC using low-power RA and in-stage redundancy technology

Speaker: Ping Yang (CCNU)

PingYang_CEPC2024.pdf

256 SiPM readout prototype design for Calorimeters

Speaker: 云起 邓 (华中师范大学)

Design of the High-Speed and Wide Dynamic Range SiPM Readout Chip_FINAL.pdf

257 A common project for detector data links

Speaker: 迪 郭 (华中师范大学)

Detector_Data_Links_2024CEPC.pdf

258 Radiation tolerance of opto-electronics and Ge-doped MM fiber

Speaker: Suen Hou (IPAS)

20241023_Opto-Hangzhou_v3b.pdf

QCD: 1

Zoom Link, ID:85910938851, Code: 848529

259 Alpha-s measurement using Z->tautau at CEPC

Speaker: Yuzhi Che (IHEP)

CEPCWS_2024.pdf

260 Alpha-s measurement using Energy Energy Correlator

Speaker: Dr Zhen Lin (ZJU)

cepc2024.pdf

261 Jet origin identification at the CEPC

Speaker: Dr Yongfeng Zhu (PKU)

zhuyf-2024CEPCWS.pdf

262 Energy Energy correlators in DIS

Speaker: Prof. Haitao Li (SDU)

haitao_ CEPC-2024.pdf

Software: 1

Zoom Link, ID:87170162344, Code:625716

263 Progress in CEPCSW Core Software

The CEPCSW is the offline data processing and analysis software being developed for the CEPC experiment, based on the Key4hep common HEP turnkey software stack. It utilizes Gaudi as its underlying framework, Edm4hep as its event data model, and DD4hep for managing detector geometry. The CEPCSW has been used to optimize detector performance and maximize physics potential, particularly in the studies related to the CEPC reference detector. This contribution will present the latest developments in the CEPCSW core software, including Gaussino-based simulation, beam-related background simulation, and the analysis framework. Additionally, it will highlight progress in various R&D activities, such as machine learning-based simulations and track reconstruction with ACTS.

Speaker: Tao LIN (高能所)

lintao-202410-CEPCSW status-v0.pdf

264 TPC Track Reconstruction in CEPCSW

CEPC will select pixelated readout to replace pad readout as the baseline of the Time Projection Chamber to obtain better PID performance. Due to ionization caused by incoming charge particle, 20-30 hits is generated on the pixelated readout within a 5x5mm area, possible to take more than one hits in same row, which goes against Kalma filter. This study employs a machine learning algorithm based on graph neural networks to merge hits within each 5x5mm area, resulting in a single hit position. Subsequently, trajectory reconstruction is performed on the merged hits in the TPC using tracking algorithms, and their performance is evaluated. The presentation will also cover the matching algorithm and performance of reconstructed trajectories in the TPC with those in the silicon detectors.

Speaker: Dr 储 王 (IHEP)

CEPC_TPC.pdf

265 Digitization of TaichuPix-3 silicon pixel detector based on AllPix-Squared framework

A telescope composed of TaichuPix-3 chips is simulated with the AllPix-Squared framework, which is an open-source software. The AllPix-squared framework is able to simulate the physical process of silicon pixel detectors and digitization of the front-end electronics. The TaichuPix-3 chips are characterised by AllPix-squared simulation and beam test results. This report will show the comparison between simulation and beam test results in cluster size and efficieny variation with the incident angle and threshold.

Speaker: 鲁函岑 LU Hancen (ihep)

BeamTestAP2Sim_talk_CEPCWS.pdf

266 CyberPFA: Crystal Bar ECAL Reconstruction in CEPC

The precise measurements of the Higgs, W and Z boson properties at future electron-positron collider will provide critical tests of the Standard Model (SM) and are essential in the exploration of new physics beyond the SM (BSM). To distinguish the hadronic decays of W and Z bosons, a 3-4% boson mass resolution(BMR) for jet systems is required. The particle flow approach, which aims to measure individual particles in jets using imaging calorimeter system, is a very promising method to achieve the unprecedented BMR.

A novel electromagnetic calorimeter (ECAL) with orthogonally arranged crystal bars has been proposed in CEPC reference TDR. The crystal bar design is expected to provide optimal intrinsic energy resolution and three-dimensional shower information for the particle flow algorithm (PFA). Additionally, the long bar design will significantly reduce the cost of electronics. However, the crystal bar ECAL also presents challenges, such as the potential ambiguity problem for multiple particles due to the perpendicular arrangement of crystal bars in adjacent layers and increased shower overlap from different particles caused by the larger $R_M$ and $X_0/λ_I$ for crystals.

This report presents recent progress on CyberPFA, a dedicated particle flow algorithm for the crystal bar ECAL. The ambiguity problem has been addressed through the implementation of multiple optimized pattern recognition approaches, while the issue of shower overlap has been mitigated by an energy splitting module. The development of CyberPFA takes into account various aspects including electronics, heat dissipation, mechanical support, and digitization processes of ECAL. The algorithm’s performance, including a boson mass resolution of approximately 3.8%, will be demonstrated. These results underscore the potential of the proposed ECAL design and the PFA in enhancing detector capabilities and reconstruction methodologies for future electron-positron collider experiments.

Speaker: Yang Zhang

CrystalECAL_Software.pdf

267 High level reconstruction with deep learning for Higgs factories

Deep learning can give a significant impact on physics performance of electron-positron Higgs factories. We are working on two topics on event reconstruction to apply deep learning; one is jet flavor tagging. We apply particle transformer to ILD full simulation to obtain jet flavor, including strange tagging. The other one is particle flow, which clusters calorimeter hits and assigns tracks to them to improve jet energy resolution. We modified the algorithm developed in context of CMS HGCAL based on GravNet and Object Condensation techniques and add a track-cluster assignment function into the network. The overview and performance of these algorithms will be presented.

Speaker: Taikan Suehara (ICEPP, The University of Tokyo)

241025-hlreco-cepcws-suehara.pdf

10:30 Coffee break

Accelerator: 10

Zoom Link, ID:84479508720, Code:925544

Convener: Wei Lu (Tsinghua University)

268 Status of HALHF

Speaker: Brian Foster (University of Oxford)

HALHF_CEPC_Hangzhou_1024.pptx

269 CEPC/SppC compatibility

Speaker: Yiwei WANG (IHEP)

SPPC_lattice_design_and_compatibility_CEPCworkshop2024_v3.pptx

270 SppC high field magnet

Speaker: Qingjin XU（remote） (高能所)

HF Magnet Program at IHEP-CAS -CEPC-Oct 2024.pdf

271 INFN-LASA Contribution to SRF based International Projects

Speaker: Daniele Sertore (I)

CEPC2024_INFN LASA.pptx

Electronics: 2

Zoom Link, ID:81317080254, Code:103003

Convener: Davide Falchieri (INFN Bologna)

272 Progress in wireless data transmission for detector readout

Speaker: Jun Hu (IHEP, CAS)

ws2024upload.pdf

273 Researches on CMOS pixel sensors with on-chip artificial neural networks

Speaker: 瑞光 赵 (西北工业大学)

Researches on CMOS pixel sensors with on-chip artificial neural networks_hangzhou.pdf

274 Pixel TPC readout electronics

Speaker: Zhi Deng (Tsinghua University)

Development of Interposer based pixel TPC readout electronics.pdf

275 A common project for powering detector front-end electronics

Speaker: 王 夏雨 (西北工业大学)

XiayuWang_CEPC2024.pdf

276 An overview of detector serial powering developments

Speaker: Mitch Newcomer (UPenn)

Serial PowerSystems_CEPC2024.pdf

277 Comparison of Electronic Systems for Precision Timing in ATLAS and CMS Experiments

Speaker: Jie ZHANG (Institute of High Energy Physics)

Comparing Electronic Systems for Precision Timing in ATLAS and CMS Experiments.pdf

QCD: 2

Zoom Link, ID:85910938851, Code: 848529

278 Fragmentation functions in e+e- collisions: CEPC vs the LEP legacy vs LHC

Speaker: Hongxi Xing (South China Normal University)

FFs-xing.pdf

279 Status of the CEPC New Physics Whitepaper

Speaker: XuAi ZHUANG (高能所)

CepcNpWp-Hangzhou2024-Xuai.pdf

Software: 2

Zoom Link, ID:87170162344, Code:625716

280 Detector and event visualization software for CEPC

Detector and event visualization software is essential for modern high-energy physics (HEP) experiments. It plays an important role in the whole life circle of any HEP experiment, from detector design, simulation, reconstruction, detector construction, and installation, to data quality monitoring, physics data analysis, education, and outreach. In this talk, we will discuss two frameworks and their potential in developing visualization software for CEPC. One is the Phoenix framework, based on the JavaScript 3D library for web-based event display. The other is based on Unity, a popular industrial platform for game development and immersive experience creation. The applications of both frameworks in HEP experiments will also be introduced.

Speaker: Mr Yujie Zeng (Sun-Yat sen university)

Detector and event visualization software for CEPC_v4.pptx

281 Jet reconstruction with quantum-annealing-inspired algorithms

Jet reconstruction is a crucial component of reconstruction in high energy collider experiments. It is known for high consumption of computing resources, and various investigations are ongoing to cope with this challenge. This reconstruction task can be considered as a quadratic unconstrained binary optimization (QUBO) problem, which is suitable to be solved with quantum algorithms. I will resent recent studies on quantum-annealing-inspired algorithms, in particular the simulated bifurcation (SB) algorithms. They can handle significantly large data at high speed; e.g. as much as four orders of magnitude faster than the simulated annealing for the track reconstruction, demonstrated in our previous study. SB also provides promising performance on jet reconstruction, which will be the scope of this talk.

Speaker: Prof. Hideki (英希) Okawa (大川) (IHEP)

okawa_CEPC2024_quantumjetreco_20241026.pdf

282 Quantum Generator for Fast Shower Simulation

High-energy physics relies on large and accurate samples of simulated events, but generating these samples with GEANT4 is CPU intensive. The ATLAS experiment has employed generative adversarial networks (GANs) for fast shower simulation, which is an important approach to solving the problem. Quantum GANs, leveraging the advantages of quantum computing, have the potential to outperform standard GANs.
Considering the limitations of the current quantum hardware, we conducted preliminary studies utilizing a hybrid quantum-classical GAN model to produce downsampled 1D(8 pixels) and 2D(64 pixels) calorimeter average shower shapes on quantum simulators. The impact of quantum noise is also investigated on the noisy simulator, and the performance is checked on the real quantum hardware.
After producing the average shower shape, we implemented a new generator model to produce the actual shower image with event fluctuation.

Speaker: Dr Xiaozhong Huang (IHEP)

Quantum GAN for fast shower simulation.pdf

283 CEPC Computing Platform Design and Vision

As high-energy physics experiments expand and precision improves, the volume of data generated has grown exponentially. The design of computing systems is therefore critical for the efficient analysis and processing of this data. This report outlines the design of the CEPC computing platform, focusing on its computing capabilities, storage solutions, and network infrastructure etc.

Speaker: Xiaowei JIANG (高能所)

CEPC Computing Platform Design and Vision-2024-hangzhou.pdf

Plenary: 3

Zoom Link, ID:85910938851, Code: 848529

Convener: Haijun Yang (Shanghai Jiao Tong University)

284 Operation status of SuperKEKB RF system

Speaker: Takafumi Okada (SOKENDAI/KEK)

2024CEPC_SuperKEKB_RF_okada.pptx

285 ECFA DRD3 and Silicon Detector Technologies

Speaker: Gregor Kramberger

02_DRD3_collaboration_GK.pdf

286 The CEPC Accelerator EDR

Speaker: Jie GAO (IHEP)

CEPC Accelerator EDR Status -V4-(CEPC workshop plenary)-J. Gao.pdf

287 TDR of A Reference CEPC Detector

Speaker: Jianchun Wang (IHEP)

241026_CEPCWS_RefTDR.pdf

16:00 Coffee break

Plenary: 4

Zoom Link, ID:85910938851, Code: 848529

Convener: Jianchun Wang (IHEP)

288 Report on Industry and Sustainability Sessions in Linear Collider Workshops

Speaker: Tohru Takahashi (Hiroshima University)

Industry and Sustainability Takahashi.pdf

289 W mass measurement

Speaker: Marco Pieri (UC San Diego)

Wmass_MPieri.pdf

Wmass_MPieri.pptx

290 Opportunities in Long-Lived Particles at Current and Future Colliders

Speaker: Zhen Liu (University of Minnesota)

25_LLP_FutureColliders_ZhenLiu_CEPC2024.pptx

291 Closing Remarks

CEPCWS2024_Closing.pdf

Sunday, 27 October

09:00 Ad hoc satellite meetings

09:00 Self-Guide Excursions