This work presents a design framework of a High-Voltage CMOS pixel sensor for high energy particle tracking, which can provide a time resolution of ~ ns order under the hit rate exceeding 100Mhz/cm2. Signal collection, amplification, and digitization are all implemented within each individual pixel. Furthermore, a pixel-level coarse-fine Time-to-Digital Converter (TDC) is also integrated into...
COFFEE3 prototype chip were fabricated with 55-nm HV-CMOS process to aim for the requirements of CEPC inner tracker.COFFEE3 including 4 sectors: 1) passive sensing diode array; 2) standalone PLL block; 3) pixel matrix with in-pixel CSA and half part of discriminator, while other circuits at the end of column; 4) pixel matrix with full in-pixel CSA, discriminator, TDC, while readout circuit at...
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 TDR specifies 96 cryomodules for 650 MHz 2-cell cavities, with each cryomodule originally housing two cavities. During the horizontal testing phase, however, we plan to simultaneously drive six superconducting...
The High Energy Photon Source (HEPS), a major national science and technology infrastructure project during the 13th Five-Year Plan period, will become one of the brightest fourth-generation synchrotron radiation sources in the world upon completion. As the core component of HEPS, the alignment precision of the pre-alignment units in the storage ring is critical for ensuring long-term stable...
This poster primarily details the design and development of a superconducting quadrupole magnet in the interaction region for the CEPC project. It focuses on the magnet design scheme based on direct winding technology. The design for the direct winding CCT magnet is described, employing the surface current method to derive the magnetic field of the CCT coil and the interference field between...
To address the requirements of CEPC inner-tracker, the COFFEE3 chip was developed using an advanced 55nm High Voltage CMOS (HV-CMOS) process for high spatial and time resolution and low power consumption,COFFEE3 is designed to validate two distinct readout architectures integrated on a single chip, focusing on verifying circuit functionality and core performance. This poster presents the...
This paper describes the design and simulation of the complete electron gun, electromagnet and RF structure of 10 MW High efficiency (75%) multibeam (06 beams) klystron for high energy physics applications. At an acceleration potential of 115 kV, a space charge beam current of total 132A is achieved with an average cathode loading of less than 3.36 A/cm2. The maximum surface electric fields at...
This paper focuses on designing S-band klystrons with higher efficiency to reduce energy consumption and costs in particle accelerators. Two novel bunching methods, Core Oscillation Method (COM) and Bunching Alignment and Collecting (BAC), have been applied to the S-band klystron at the Beijing Electron Positron Collider II (BEPCII). These methods have increased the klystron's efficiency from...
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...
For the pre-study of the Super Proton-Proton Collider (SPPC) project, the Institute of High Energy Physics (IHEP) has developed the LPF3-U, designed to achieve a 16 T dipole field within a 30 mm aperture. The LPF3-U magnet integrates six Nb3Sn coils in a Common-Coil configuration, accompanied by an HTS insert that utilizes seven YBCO tapes wound in parallel with a stainless-steel tape in a...
Several high-field dipole magnets have been developed at the Institute of High Energy Physics, Chinese Academy of Sciences (IHEP, CAS) for preliminary research on next-generation high-energy colliders such as the Super Proton-Proton Collider (SPPC), Future Circular Collider (FCC), and others. Following the achievement of a 12.47-T main field at 4.2 K by the LPF1-U magnet in 2021, IHEP is...
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...
For large particle accelerators, the radio-frequency (RF) power source system constitutes the most significant portion of total energy consumption. A substantial fraction of the RF energy not utilized for charged particle acceleration is directed to an absorption load at the output of the accelerating structure, where it is converted into thermal energy and dissipated. To use this otherwise...
High-voltage pulse modulator is a key device in linear accelerators, serving as the intermediate link that converts power from the power supply into microwave power. According to the CEPC technical design, the linear accelerator requires 236 sets of C-band 80 MW power source systems to supply 5712 MHz/3 μs/100 Hz pulsed power to the accelerating structures. To achieve the target klystron...
The CEPC detector requires a superconducting magnet to provide a deflection magnetic field for secondary particles. The central field strength of the superconducting magnet is 3 T. The inner diameter of the magnet is 7.07 m, its length is 8.5 m, and its thickness is approximately 0.75 m. Based on the low-temperature superconducting cable scheme, this paper calculates the magnetic field...
For the average output power of the C-band klystron for CEPC LINAC, the power capacity and stability of the collector are investigated. The characteristics of the electron collection, the modeling of the cooling system, and the suppression of the magnetic field are analyzed. The dissipated power is associated with the transverse energy of the electron beam guided by the applied magnetic field...
The RF power source system is a critical component of the CEPC, providing the high energy required to accelerate positrons and electrons in order to compensate for energy losses due to synchrotron radiation and interactions between the beam and cavity impedance. Its reliability and stability directly affect the operational efficiency of the entire facility. Based on operational experience from...
Pioneering R&D in HVCMOS pixel sensors at the advanced 55 nm process, the COFFEE series prototypes are currently being developed for the CEPC inner tracker and Upstream Pixel tracker (UP) in the LHCb Upgrade II. COFFEE3, the latest prototype with two distinct readout architecture, was design and fabricated in 2025. Though featuring a small-scale prototype (3×4 mm2), COFFEE3 is designed to...
To meet the particle detection requirements of next-generation high-energy physics experiments, the AC-Coupled Low Gain Avalanche Diodes (AC-LGADs) have emerged as a breakthrough technology. While retaining the exceptional temporal resolution of standard Low Gain Avalanche Diodes (LGADs), it ingeniously incorporates position sensitivity through its unique resistive n+ layer and capacitively...
The baseline design for the CEPC linac has been established at 30 GeV, employing S-band and C-band normal-conducting accelerating structures (AS). From 1.1 GeV to 30 GeV after the damping ring, there are 235 sets of C-band units with pulse compressors. A C-band high-power test bench will be established in Huairou Park at IHEP.
This study concentrated on optimizing cavity shape for a C-band...
Improving klystron efficiency is crucial for reducing the operational costs of particle accelerators. This study presents an S-band 50 MW periodic permanent magnet (PPM) focusing high-efficiency klystron , aiming to minimize energy consumption while maintaining high conversion efficiency. The research addresses the domestic need for localized development of S-band 50 MW klystrons. A key focus...
Abstract: The baseline design for the CEPC linac has been established at 30 GeV, employing S-band and C-band normal-conducting accelerating structures (AS). From1.1GeV to 30GeV after the damping ring, there are 235 sets C-band units with pulse compressors. A C-band high-power test bench will be established in Huairou Park at IHEP. A C-band (5712 MHz) spherical cavity pulse compressor have...
This study employs the SAD program to perform particle tracking simulations of the multi-turn injection process in the SuperKEKB Low-Energy Ring (LER). By tracking large numbers of particles, we quantitatively analyze the beam loss distribution and identify the primary sources of particle loss during injection. The results provide a detailed understanding of the factors limiting the injection...
