Broad excitations in a 2+1D overoccupied gluon plasma
Abstract
Motivated by the initial stages of highenergy heavyion collisions, we study excitations of farfromequilibrium 2+1 dimensional gauge theories using classicalstatistical lattice simulations. We evolve field perturbations over a strongly overoccupied background undergoing selfsimilar evolution. While in 3+1D the excitations are described by hardthermal loop theory, their structure in 2+1D is nontrivial and nonperturbative. These nonperturbative interactions lead to broad excitation peaks in spectral and statistical correlation functions. Their width is comparable to the frequency of soft excitations, demonstrating the absence of soft quasiparticles in these theories. Our results also suggest that excitations at higher momenta are sufficiently longlived, such that an effective kinetic theory description for 2+1 dimensional Glasmalike systems may exist, but its collision kernel must be nonperturbatively determined.
 Publication:

Journal of High Energy Physics
 Pub Date:
 May 2021
 DOI:
 10.1007/JHEP05(2021)225
 arXiv:
 arXiv:2101.02715
 Bibcode:
 2021JHEP...05..225B
 Keywords:

 Lattice QCD;
 QuarkGluon Plasma;
 Perturbative QCD;
 High Energy Physics  Phenomenology;
 High Energy Physics  Lattice;
 Nuclear Theory
 EPrint:
 33 pages, 11 figures