Sphaleron rate in lattice gluodynamics

Abstract

QCD vacuum can be treated as a series of energetically equivalent, but topologically distinct sectors. The rate of transitions between various topological sectors is determined by the sphaleron rate ΓCS. This quantity is given by the limits of zero frequency and zero momentum of the correlator of topological charge density. Sphaleron rate is very similar to such transport coefficients as viscosity or conductivity. Sphaleron rate also describes time relaxation of the chiral charge. In this report we discuss the measurement of sphaleron rate in lattice gluodynamics in the deconfinement phase. We use Gradient Flow to measure the topological charge density correlator, and we also take continuum limit. We provide an estimation of the sphaleron rate in lattice gluodynamics and compare it with results obtained by other methods.