Balance function as a unique probe to the quark gluon plasma: overview and outlook

by JINJIN PAN (Wayne State University)

Tuesday 25 Feb 2020, 11:00 → 12:00 US/Eastern

Small Seminar Room

In relativistic heavy-ion collisions, correlations of hadrons with opposite quantum numbers provide insight into general charge creation mechanisms, the time scales of quark production, collective motion of the Quark Gluon Plasma (QGP), and re-scattering in the hadronic phase. The longitudinal and azimuthal widths of general charge balance functions for charged pion ($\pi^{\pm}$), kaon ($K^{\pm}$) and (anti-)proton ($p/\bar{p}$) are used to examine the two-wave quark production scenario recently proposed to explain quark-antiquark productions within the QGP, which predicts a large increase in up and down quark pairs relative to strange quark pairs around the time of hadronization. Balance function as a function of relative azimuthal angle is a good probe to the diffusion effect, which is a signature of the QGP. In addition, the balance function integrals measure hadron pairing probabilities, which provide a key constraint for hadron productions in models. Furthermore, balance function is also a key observable to study net-proton fluctuations and the Chiral Magnetic Effect (CME).

In this talk, I will present a state-of-the-art overview on experimental measurements of balance function by STAR and ALICE, along with an outlook for the future experimental measurements.

AuAu_20200225_BNL_BF_v5.pdf