Instabilities of an anisotropically expanding non-Abelian plasma:3D+3Vdiscretized hard-loop simulations

Abstract

We study the (3+1)-dimensional evolution of non-Abelian plasma instabilities in the presence of a longitudinally expanding background of hard particles using the discretized hard loop framework. The free streaming background dynamically generates a momentum-space anisotropic distribution which is unstable to the rapid growth of chromomagnetic and chromoelectric fields. These fields produce longitudinal pressure that works to isotropize the system. Extrapolating our results to energies probed in ultrarelativistic heavy-ion collisions we find, however, that a pressure anisotropy persists for a few fm/c. In addition, on time scales relevant to heavy-ion collisions we observe continued growth of plasma instabilities in the strongly non-Abelian regime. Finally, we find that the longitudinal energy spectrum is well-described by a Boltzmann distribution with increasing temperature at intermediate time scales.

Basin of attraction for turbulent thermalization and the range of validity of classical-statistical simulations

“…The early-time behavior is then described by plasma instabilities, which have been intensively analyzed over the past years [19][20][21][22]. Classical-statistical simulations show that gluons become highly occupied ∼ 1/α s (Q) after a proper time ∼ Q −1 log 2 (α −1 s ) for expanding systems [23][24][25].…”

Three-loop HTLpt thermodynamics at finite temperature and chemical potential

“…Quantities such as the dilepton production rate [96,97], photon production rate [98], single quark and quark anti-quark potentials [99][100][101][102][103][104][105][106][107], fermion damping rate [108][109][110], photon damping rate [111], gluon damping rate [112,113], jet energy loss [114][115][116][117][118][119][120][121][122][123][124][125], plasma instabilities [126][127][128][129][130][131][132], thermal axion production [133], and lepton asymmetry during leptogenesis [134,135] have also been calculated using HTLpt. We note, however, that most of the papers above have only worked at what we would call leading order in HTLpt.…”

Collective excitations of hot QCD medium in a quasiparticle description

“…There has been various attempts to study them both in the isotropic and anisotropic hot QCD medium [17][18][19][20]. The distributions functions for partons, used to study different aspects of QGP are discussed in [21][22][23][24][25]. In most of the studies, the momentum distributions that are crucial to obtain the whole plasma spectrum have been modeled by considering the QGP as free ultra-relativistic gas of quarks and gluons.…”