Lepton identification at particle flow oriented detector for the future e⁺e^- Higgs factories

The lepton identification is essential for the physics programs at high-energy frontier, especially for the precise measurement of the Higgs boson. For this purpose, a toolkit for multivariate data analysis (TMVA) based lepton identification (LICH) has been developed for detectors using high granularity calorimeters. Using the conceptual detector geometry for the Circular Electron–Positron Collider (CEPC) and single charged particle samples with energy larger than 2 GeV, LICH identifies electrons/muons with efficiencies higher than 99.5% and controls the mis-identification rate of hadron to muons/electrons to better than 1/0.5%. Reducing the calorimeter granularity by 1–2 orders of magnitude, the lepton identification performance is stable for particles with E> 2 GeV. Applied to fully simulated eeH/μμH events, the lepton identification performance is consistent with the single particle case: the efficiency of identifying all the high energy leptons in an event, is 95.5–98.5%.