Holographic phase diagram of quark-gluon plasma formed in heavy-ions collisions

TL;DR

This paper constructs a holographic model to map the phase diagram of quark-gluon plasma formed in heavy-ion collisions, linking trapped surface formation to QGP phases and analyzing effects of chemical potential.

Contribution

It introduces a holographic dual model for heavy-ion collisions using charged shock waves to explore the QGP phase diagram and effects of chemical potential.

Findings

Non-zero chemical potential reduces collision multiplicity.

Qualitative agreement between different holographic models.

Phase diagram mapped via trapped surface formation in dual gravity models.

Abstract

The phase diagram of quark gluon plasma (QGP) formed at a very early stage just after the heavy ion collision is obtained by using a holographic dual model for the heavy ion collision. In this dual model colliding ions are described by the charged shock gravitational waves. Points on the phase diagram correspond to the QGP or hadronic matter with given temperatures and chemical potentials. The phase of QGP in dual terms is related to the case when the collision of shock waves leads to formation of trapped surface. Hadronic matter and other confined states correspond to the absence of trapped surface after collision. Multiplicity of the ion collision process is estimated in the dual language as area of the trapped surface. We show that a non-zero chemical potential reduces the multiplicity. To plot the phase diagram we use two different dual models of colliding ions, the point and the wall shock waves, and find qualitative agreement of the results.