Directed, Elliptic and Triangular Flows in Asymmetric Heavy Ion Collisions

Abstract

In this paper we propose to thoroughly investigate asymmetric nuclear collisions both in the fixed target mode at the laboratory energy below 5 GeV per nucleon and in the collider mode with a center of mass energy below 11 GeV per nucleon. Using the UrQMD transport model, we demonstrate a strong enhancement of directed and elliptic flow coefficients for the midcentral asymmetric nuclear collisions compared to symmetric collisions. We argue that such an enhancement is due to the disappearance of the nuclear shadowing effect on the side of the smaller projectile nucleus. An analysis of the energy and centrality dependencies of the directed, elliptic and triangular flows at midrapidity shows us their sensitivity to the details of the employed model of hadronic interaction. In general, the flow patters found for asymmetric nuclear collisions have a very rich and complicated structure of energy and centrality dependencies compared to the flows found for symmetric collisions and are worth to be investigated experimentally. The directed, elliptic, and triangular flow coefficients are computed for target nuclei containing high density fluctuations and thoroughly compared with that ones obtained in the absence of such fluctuations.

Fluctuating Glasma Initial Conditions and Flow in Heavy Ion Collisions

“…A large uncertainty in the hydrodynamical description of ultrarelativistic heavy ion collisions is our imperfect knowledge of multi-gluon states in the nuclear wavefunctions and the early-time dynamics of gluon fields after the collision. In heavy ion collisions, studies of observables sensitive to harmonics of hydrodynamic flow distributions provide constraints both on the low shear viscosity of the Quark-Gluon Plasma (QGP) and the initial state dynamics [1][2][3][4][5][6][7][8]. This situation is analogous to studies of the cosmic microwave background [9], wherein inhomogeneities in the observed power spectrum are sensitive to primordial quantum fluctuations.…”

Triple high energy nuclear and hadron collisions - a new method to study QCD phase diagram at high baryonic densities

“…Moreover, in this case for reliable modeling of the TNC at low collision energies, it will be also necessary to reformulate the equations of relativistic hydrodynamics and hydro-kinetics according to the correct equations of energy-momentum and charge conservations [75,76] which are mathematically consistent with the boundary (kinetic freeze-out) conditions. Besides, an experimental detection and theoretical modeling of the elliptic, triangular and higher order flow patterns [77,78] for the TNC may be another challenge for the HENP community.…”