The 2025 International Workshop on the High Energy Circular Electron Positron Collider

The QED Bhabha interaction is the most precisely predicted approaching 10^-4 precision as the reference channel for Luminosity measurement at the e+e- collider experiments. The BHLUMI generator developed at LEP is employed for the LumiCal proposed for the CEPC Higgs factory requiring minimum systematics errors to 10^-3 at Higgs mass and 10^-4 at Z-pole. Bhabha events shall be measured to...

The HCAL serves as the key detector component through its essential role in jet energy reconstruction within the PFA paradigm. Key features of engineering design include an optimized material composition that achieves the 30% sampling fraction while minimizing the proportion of non-sensitive material. The 16 trapezoidal sectors in the barrel and in the matching endcap disks implement the same...

This study addresses the design challenges of the barrel yoke, a key detector component in the large-scale Circular Electron Positron Collider (CEPC) scientific facility. Given the detector's unprecedented size and extreme demands for structural strength and precision, a conventional barrel yoke design would fail to meet the requirements. Consequently, an self-supporting scheme of barrel yoke...