Chiral symmetry breaking and chemical equilibrium in a heavy-ion collisions

Abstract

We examine the thermalization of an ensemble of the octet of pseudoscalar mesons, in the isospin symmetric limit, whose interactions are constrained through chiral symmetry, unitarity, and measurements. The reaction amplitudes generate all resonances up to masses of about 2 GeV, with twelve input parameters, namely f_pi, three masses, and eight low energy constants (LECs) of chiral perturbation theory. In linear response theory, we find that matter takes an extremely long time to thermalize. These long relaxation times are directly related to the fact that these mesons are pseudo-Goldstone bosons of chiral symmetry breaking. This result indicates that fireballs created with zero baryon number in heavy-ion collisions will drop out of chemical equilibrium once they enter the chiral symmetry broken phase.

References in corpus (6)

• The QCD transition temperature: results with physical masses in the continuum limit II.
• Rapid hydrodynamic expansion in relativistic heavy-ion collisions
• Transverse-momentum spectra of strange particles produced in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV in the chemical non-equilibrium model
• Hadron Resonance Gas Model for An Arbitrarily Large Number of Different Hard-Core Radii
• Chemical nonequilibrium for interacting bosons: applications to the pion gas
• Freeze-out and thermalization in relativistic heavy ion collisions

Cited by in corpus (1)

• Study of freeze-out dynamics of strange hadrons