Revisiting the Gluon Spectrum in the Boost-Invariant Glasma from a Semi-Analytic Approach

Understand

In high energy heavy-ion collisions, the degrees of freedom at the very early stage can be effectively represented by strong classical gluonic fields within the Color Glass Condensate framework.

• As the system expands, the strong gluonic fields eventually become weak such that an equivalent description using the gluonic particle degrees of freedom starts to become valid.
• We revisit the spectrum of these gluonic particles by solving the classical Yang-Mills equations semi-analytically with the solutions having the form of power series expansions in the proper time.
• We propose a different formula for the gluon spectrum which is consistent with energy density during the whole time evolution.