Charged energy correlators in small systems with ALICE
Minyoung Hwang
TL;DR
This work introduces charged energy–energy correlators (EECs) as a charged extension of the energy-weighted two-particle correlator in jets, enabling direct probes of energy and charge flow during hadronization. Using ALICE data from pp and p--Pb collisions at 5.02 TeV, the study measures charged EECs and compares them to multiple hadronization models, showing that the charge-weighted observable Sigma_EEC^Q provides the strongest model discrimination and that current MC generators struggle to describe all data, especially in the confinement region. The results reveal a charge-independent modification between p--Pb and pp and demonstrate the potential of charged EECs to constrain hadronization mechanisms and cold nuclear matter effects, particularly at low jet p_T. The findings motivate future explorations in larger systems and with quark-enriched jet samples to further refine our understanding of energy and charge transport in jet fragmentation.
Abstract
Energy-energy correlators (EECs), which are energy-weighted cross-sections of particle pairs, offer incisive probes into QCD dynamics, across the full scale of jet evolution, by separating energy scales in the jet fragmentation through the angular distance of the resulting particle pairs. Charged EECs probe the energy flux carried by pairs of the same or opposite electric charges. The interplay between energy distribution and charge conservation enables charged EECs to provide novel constraints on hadronization mechanisms. We present the first measurements of two-point charged energy correlators of inclusive jets in pp collisions at $\sqrt{s} = 5.02$ TeV using the ALICE detector, and compare them with hadronization models to investigate different confinement mechanisms. We also present measurements in p-Pb collisions, examining cold nuclear matter effects on jet evolution.