Jet-associated Balance Functions of Charged and Identified Hadrons in pp Collisions at $\sqrt{s}=13.6$ TeV using PYTHIA8

Abstract

We present a study of charge balance functions inside jets in proton-proton collisions at $\sqrt{s}=13.6$ TeV using the PYTHIA8 event generator. The balance function is a differential observable of opposite-charge correlations, which is calculated in the jet frame for inclusive charged hadrons and the identified $π$, $K$, and $p$. The results show a clear narrowing of the balancing width with increasing jet charged multiplicity, indicating that particle production becomes more localized in momentum space in high-multiplicity jets.This trend resembles features attributed to collective expansion in heavy-ion collisions. The species dependence highlights sensitivity to the redistribution of strangeness and baryon number during string fragmentation and color reconnection. The new CR tune yields a little broader proton balance-function width in $Δϕ^{*}$ than CP5, hinting at enhanced baryon-production dynamics, whereas meson widths differ only mildly. These comparisons suggest that multiparton interactions and color reconnection contribute to the observed trends, potentially generating collective like features inside jets, especially in high multiplicity jets, via nontrivial color dynamics alongside standard fragmentation. Taken together, the results establish identified hadron balance functions in high multiplicity jets as a sensitive probe of hadronization and provide new constraints for models of small system collectivity.