# 54. International Winter Meeting on Nuclear Physics

25-29 January 2016
Bormio, Italy
Europe/Berlin timezone

## Modelling Early Stages of Relativistic Heavy Ion Collisions: Coupling Relativistic Transport Theory to Decaying Color-Electric Flux Tubes

25 Jan 2016, 17:15
3m
Bormio, Italy

#### Bormio, Italy

Poster Relativistic Heavy Ion Physics

### Speaker

Mrs Lucia Oliva (INFN-Laboratori Nazionali del Sud, University of Catania)

### Description

In this study we model early times dynamics of relativistic heavy ion collisions by an initial color electric field which then decays to a plasma by the Schwinger mechanism, coupling the dynamical evolution of the initial color field to the dynamics of the many particles system produced by the decay. The latter is described by relativistic kinetic theory in which we fix the ratio $eta/s$ rather than insisting on specific microscopic processes, and the backreaction on the color field is taken into account by solving self-consistently the kinetic and the field equations. Within a single self-consistent calculation scheme we address the problems of isotropization and thermalization of the quark-gluon plasma produced by the field decay, as well as the quark-gluon plasma formation time and its chemical equilibration, both for 1+1D and 3+1D expanding geometry. We find that regardless of the viscosity of the produced plasma, longitudinal pressure becomes positive within 0.2 fm/c. The initial color electric field decays within 1 fm/c; however in the case $eta/s$ is large plasma oscillations appear and affect the entire time evolution of the system. In case of small $eta/s$ ($eta/s$<0.3) we find that the isotropization time is approx. 0.8 fm/c and the thermalization time is approx. 1 fm/c. Moreover quark-gluon plasma production occurs in less than 1 fm/c, and almost perfect chemical equilibration takes place within 1 fm/c. Hence our work supports the common assumptions of hydrodynamics about thermalization, isotropization and equilibration of quark-gluon plasma.

### Primary author

Mrs Lucia Oliva (INFN-Laboratori Nazionali del Sud, University of Catania)

### Co-authors

Mr Armando Puglisi (Università degli Studi di Catania, Laboratori Nazionali del Sud) Dr Francesco Scardina (University of Catania, INFN-Laboratori Nazionali del Sud) Dr Marco Ruggieri (University of Catania) Dr Salvatore Plumari (University of Catania, INFN-Laboratori Nazionali del Sud) Prof. Vincenzo Greco (University of Catania, INFN-Laboratori Nazionali del Sud)

 Slides