Speaker
Description
Next-generation electron–positron colliders (CEPC, FCC-ee, ILC) demand excellent particle identification (PID) to fulfill their precision physics programs, particularly in flavor physics. The Time Projection Chamber (TPC), adopted as the main tracking detector in all baseline designs, must simultaneously achieve high-granularity readout for PID and maintain robust performance under high-luminosity beam-induced backgrounds. These intertwined challenges—micro-scale readout optimization and macro-scale background mitigation—represent central, shared R&D priorities for the global DRD1 and TPC detector communities.
This contribution presents our integrated R&D program addressing both fronts. Using a full Geant4/Garfield++ simulation chain, we systematically optimize pad sizes (55–500 μm) to maximize PID performance via traditional dE/dx and dN/dx cluster-counting methods, implementing a layered truncated-mean algorithm to suppress delta-electron effects; a full-drift-length (2.9 m) TPC prototype with Micromegas modules and TEPIX readout chips is under commissioning to validate these predictions. Concurrently, we evaluate beam-background effects using a Geant4-based simulation scheme equivalent to that adopted by the FCCee collaboration, identifying secondary low-energy photons as the dominant space-charge source under Higgs and low-luminosity Z operation modes. An optimized interaction-region design constrains the space-charge density below 1.0 nC/cm², limiting electron-drift deviations to within 100 μm over most of the TPC volume, while dedicated correction algorithms restore momentum-resolution performance. These combined studies provide essential technical guidance for TPC applications in future high-energy collider experiments.