HYDJET++ model for the ultra-relativistic heavy-ion collisions: new results and developments

Abstract

HYDJET++ model combines the description of soft processes with the treatment of hard partons propagating medium. The model is employed for the analysis of PbPb collisions at LHC energies, particularly, the azimuthal anisotropy phenomena, flow, femtoscopy, hard probes. The influence of geometric and dynamical anisotropies on the development of flow harmonics and, simultaneously, on the second- and third-order oscillations of femtoscopy radii were studied. The interplay of soft hydro-like processes and jets is able to describe the violation of the mass hierarchy of meson and baryon elliptic and triangular flows at transverse momentum pT>2 GeV/c, the fall-off of the anisotropic flow harmonics at intermediate transverse momenta, and the worsening of the number-of-constituent-quark (NCQ) scaling of elliptic/triangular flow at LHC compared to RHIC energies. The cross-talk of elliptic and triangular flows leads to emergence of higher order harmonics in the model and to appearance of ridge structure in dihadron angular correlations in a broad pseudorapidity range. Recently, the model was further extended to describe quantitatively the event-by-event fluctuations of the anisotropic flow. The model calculations agree well with the experimental data.