Speaker
Description
In recent years, several next‑generation large‑scale scientific facility plans based on electron‑positron colliders have been successively launched in the field of international high‑energy physics (FCCee, CEPC, ILC, etc.). In the published conceptual designs of accelerators and detectors, the Time Projection Chamber (TPC) is widely selected as the main tracking detector owing to its unique technical advantages. The potential impact of beam background on the TPC drift electric field uniformity under high‑luminosity operating conditions is an important research direction that requires careful evaluation. Detailed studies in collaboration with the MDI collaboration are necessary to fully assess this aspect for the application of TPCs in future high‑energy collider experiments.
This study systematically evaluates beam-background effects on high-granularity readout Time Projection Chamber Detection technology for future electron-positron colliders, using a Geant4-based background simulation scheme equivalent to that adopted by the FCCee collaboration. A comprehensive framework covering multiple space-charge sources is developed, together with theoretical models for space-charge density, electric-field distortion, and electron-drift deviation. Secondary low-energy photons generated by beam background are identified as the primary space-charge source, with key physical parameters quantified under both Higgs and low-luminosity Z operation modes. An integrated solution combining interaction-region design optimization and dedicated correction algorithms is proposed to address the associated momentum-resolution effects. The optimized CEPC interaction-region design constrains the space-charge density below 1.0 nC/cm², keeping electron-drift deviations within 100 μm over most of the TPC chamber, while the correction algorithm effectively restores momentum-resolution performance. These results provide important theoretical and technical support for TPC applications in future high-energy collider experiments.
