Di-hadron azimuthal correlation and Mach-like cone structure in a parton/hadron transport model

Abstract

In the framework of a multi-phase transport model (AMPT) with both partonic and hadronic interactions, azimuthal correlations between trigger particles and associated scattering particles have been studied by the mixing-event technique. The momentum ranges of these particles are 3 < p has been observed in correlation functions for central collisions. By comparing scenarios with and without parton cascade and hadronic rescattering, we show that both partonic and hadronic dynamical mechanisms contribute to the Mach-like structure of the associated particle azimuthal correlations. The contribution of hadronic dynamical process can not be ignored in the emergence of Mach-like correlations of the soft scattered associated hadrons. However, hadronic rescattering alone cannot reproduce experimental amplitude of Mach-like cone on away-side, and the parton cascade process is essential to describe experimental amplitude of Mach-like cone on away-side. In addition, both the associated multiplicity and the sum of p T decrease, whileas the p T increases, with the impact parameter in the AMPT model including partonic dynamics from string melting scenario.

Beam energy dependence of elliptic and triangular flow with the AMPT model

“…[12] and showed that within the AMPT model, the final momentum space anisotropy for v 3 was proportional to the initial ε 3,part [13]. This explained the previous observation that the AMPT model produced correlations similar to those seen in the data (albeit with smaller amplitudes) [14]. Later studies showed that with changes to the input parameters, AMPT could quantitatively describe the centrality dependence of v 2 and v 3 at 200 GeV and 2.76 TeV [15].…”

Nuclear cluster structure effect on elliptic and triangular flows in heavy-ion collisions

“…AMPT has been extensively applied to simulate heavy-ion collisions in a wide colliding energy range from the SPS to the LHC, which contains the initial conditions from the HIJING model [46,47], partonic interactions modelled by a parton cascade model (ZPC) [48], hadronization in a simple quark coalescence model, and hadronic rescattering simulated by a relativistic transport (ART) model [49]. AMPT is successful to describe physics in relativistic heavy-ion collision for the RHIC [45] and the LHC energies [50], including pion-pair correlations [51], di-hadron azimuthal correlations [52] as well as collective flow etc [53,54].…”

Longitudinal broadening of near-side jets due to parton cascade

“…Therefore, the melting AMPT model is much more appropriate than the default AMPT model, especially when the energy density is much higher than the critical density for the QCD phase transition. But in these previous studies with the melting AMPT model [16,21,23,24], parton cascade process does not stop until partons cease to interact, and the hadronization takes place dynamically during the process. It is not reasonable since partonic matter has a limited evolutiontime which depends on when the energy density (temperature) of reaction system enters the critical threshold, in a Lattice QCD context [25].…”

“…Details of the AMPT model can be found in a recent review [16]. As shown in previous studies about elliptic flow [16,21,23] and Mach cone-like structure [24], the partonic effect can not be neglected in the relativistic heavy-ion collisions. Therefore, the melting AMPT model is much more appropriate than the default AMPT model, especially when the energy density is much higher than the critical density for the QCD phase transition.…”