Speaker
Description
The two-wave quark production scenario can be investigated experimentally by measurements of balance functions of identified particle pairs [1]. By studying the balance functions of several hadronic species, one can gain insight into the chemical evolution of the QGP and radial flow. In a picture of early hadronization, pairs of particles and anti-particles (created at the same spacetime point) can separate further in rapidity due to the higher initial temperature and diffusive interactions with other particles. Therefore delayed hadronization will lead to strong correlations in rapidity in the final state. We present measurements of such balance functions based on an analysis of data acquired at the Large Hadron Collider (LHC) by the ALICE detector. Balance functions have been measured for identified charged-pion pairs in Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV. These balance functions are presented in relative rapidity $\Delta$y, relative pseudorapidity $\Delta\eta$, and relative azimuthal angle $\Delta\varphi$. We observe that the charged-pion balance function widths in $\Delta\eta$, $\Delta$y and $\Delta\varphi$ are narrower in central Pb-Pb collisions compared to peripheral collisions. In addition, a comparison between the balance functions of charged pions and unidentified charged particles will be shown. The findings in this analysis are consistent with the effects of delayed hadronization and radial flow, as well as the two-wave scenario.
[1] Pratt, Phys. Rev. C 85 (2012) 014904
| Experimental Collaboration | ALICE |
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