Towards a Long Strip AC-LGAD Detector for the CEPC Outer Silicon Tracker

• Mei Zhao (高能所, IHEP)

Room: Natal Convention Center The Circular Electron–Positron Collider (CEPC) is designed to reach a center-of-mass energy of up to 360 GeV for electron–positron collisions, with primary goals of precision studies of the Higgs boson and searches for physics beyond the Standard Model. The CEPC outer silicon tracker will feature a total active area of ~85 m² and will integrate advanced long microstrip AC-Coupled Low-Gain Avalanche Diode (AC-LGAD) sensors with a spatial resolution of about 10 μm, enabling per-mille-level momentum resolution for charged-particle tracking below 100 GeV/c. In addition, this detector will serve as a high-precision time-of-flight system for particle identification, targeting a single-layer timing resolution of 50 ps. Following the release of the Reference Technical Design Report (Ref-TDR), the project has entered a new R&D phase, during which high-performance sensors, readout ASICs, front-end electronics, mechanical structures, and CO₂ cooling systems are being actively developed. This report provides a comprehensive overview of the detector concept, the current status of system development, and future plans. In particular, we highlight the latest developments of the microstrip AC-LGAD sensor and its dedicated readout ASIC, LATRIC. ACCEPTED ORAL REHEARSAL