Speaker
Description
We investigate the relative importance of initial and final state effects on azimuthal correlations in low and high multiplicity p+Pb collisions at LHC energies. By matching the classical Yang-Mills dynamics of pre-equilibrium gluon fields (IP-GLASMA) to a perturbative QCD based parton cascade for the final state evolution (BAMPS) on an event-by-event basis, we find that signatures of both the initial state correlations and final state interactions are seen in azimuthal correlation observables, such as $v_2\{2P C\}(p_T)$, with their relative strength depending on the event multiplicity and transverse momentum. Initial state correlations dominate elliptic flow in low multiplicity events for transverse momenta $p_T > 2~\mathrm{GeV}$. While final state interactions are dominant in high multiplicity events and at low momenta, we find that initial state correlations strongly affect $v_2\{2P C\}(p_T)$ for $p_T>2$ GeV as well as the pT integrated $v_2\{2P C\}$. By carrying out a systematic multiplicity scan, we can also probe the dynamics on the border of initial state dominated to final state dominated - but not yet fully developed hydrodynamic – regime. We predict at which multiplicity and transverse momentum many-body QCD effects in the initial state can be experimentally unveiled.
Reference: Greif, Greiner, Schenke, Schlichting, Xu: Phys. Rev. D 96, 091504, 2017
| Content type | Theory |
|---|---|
| Centralised submission by Collaboration | Presenter name already specified |
