Anomalous Gluon Production and Condensation in Glasma

TL;DR

This paper investigates the rapid decay of color electric fields and the formation of gluon condensates in the Glasma state after high-energy heavy ion collisions, highlighting anomalous gluon production mechanisms.

Contribution

It introduces the analysis of Nielsen-Olesen unstable modes and their role in gluon production and condensation, providing new insights into Glasma dynamics.

Findings

Gluon production via Nielsen-Olesen modes is significantly enhanced.

The color electric field decays rapidly, with lifetime ~ inverse saturation momentum.

A zero-momentum mode forms a Bose condensate that grows to a large density.

Abstract

The collinear color electric and magnetic fields have been discussed to be produced immediately after high energy heavy ion collisions. We discuss anomalous gluon production under the background gauge fields. The gluons are Nielsen-Olesen unstable modes. The production rate of the modes by Schwinger mechanism has recently been found to be anomalously larger than the rate of quarks or other stable gluons. Analyzing classical evolutions of the modes with initial conditions given by vacuum fluctuations, we find that their production makes the color electric field decay very rapidly. The life time of the field is approximately given by the inverse of saturation momentum in the collisions. We also show that the mode with zero momentum form a Bose condensate and its gluon number density grows up to be of the order of $1/\alpha_g$. After the saturation of the gluon number density, the condensate melts into quark gluon plasma owing to nonlinear interactions in QCD.