Jet charge identification in the e+e− → Z → $$ \textrm{q}\overline{\textrm{q}} $$ process at Z pole

Abstract

Accurate jet charge identification is essential for precise electroweak and flavor measurements at the high-energy frontier. We propose a novel method called the Leading Particle Jet Charge method (LPJC) to determine the jet charge based on information of the leading charged particle. Tested on Z →$$ b\overline{b} $$ b b ¯ and Z →$$ c\overline{c} $$ c c ¯ samples at center-of-mass energy of 91.2 GeV, the LPJC achieves an effective tagging power ϵeff of 20%/9% for c/b jet, respectively. In combination with the Weighted Jet Charge method (WJC), we develop a Heavy Flavor Jet Charge method (HFJC), which achieves an effective tagging power ϵeff of 39%/20% for c/b jet, respectively. This paper also discusses the dependencies between jet charge identification performance and the fragmentation process of heavy flavor jets, as well as critical detector performances.