Multiplicity and transverse momentum evolution of charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions at the LHC

We report measurements of two-particle charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions at root sNN = 7, 5.02, and 2.76 TeV, respectively, as a function of pseudorapidity and azimuthal angle differences. These measurements, carried out using the balance function, probe the charge creation time and the development of collectivity in the produced systems. The balance function is studied as a function of the event multiplicity as well as the transverse momentum (p(T)) of charged particles detected in the range vertical bar eta vertical bar < 0:8. In the low transverse momentum region, 0:2 < p(T) < 2:0 GeV/c, the balance function becomes narrower in both Delta eta and Delta phi directions in all three systems for events with higher multiplicity. For higher values of transverse momenta, the balance function becomes even narrower but exhibits no significant multiplicity dependence, indicating that the observed narrowing with increasing multiplicity at low p(T) is a feature of bulk particle production.