Initial Conditions with Flow from a McLerran Venugopalan model with Transverse Dynamics

TL;DR

This paper develops a recursive analytical approach to model initial gluon fields in heavy ion collisions, incorporating transverse dynamics and flow, providing detailed initial conditions for hydrodynamic simulations.

Contribution

It extends the McLerran-Venugopalan model to include transverse coordinate-dependent charge densities and derives explicit solutions for gluon fields and energy momentum tensor up to 4th order in proper time.

Findings

Analytic expressions for gluon fields and energy momentum tensor up to 4th order in τ.

Inclusion of transverse charge density variations in initial condition modeling.

Calculation of radial, elliptic, and directed flow of gluon fields.

Abstract

Using a recursive solution of the Yang-Mills equation, we calculate analytic expressions for the gluon fields created in ultra-relativistic heavy ion collisions at small times $\tau$. We have worked out explicit solutions for the fields and the energy momentum tensor up to 4th order in an expansion in $\tau$. We generalize the McLerran-Venugopalan model to allow for a systematic treatment of averaged charge densities $\mu^2$ that vary as a function of transverse coordinates. This allows us to calculate radial, elliptic and directed flow of gluon fields. Our results can serve as initial conditions for hydrodynamic simulations of nuclear collisions that include initial flow.