Topological Susceptibility in N_f = 2 QCD at Finite Temperature

Abstract

We study the topological charge in N f = 2 QCD at finite temperature using Möbius domain-wall fermions. The susceptibility χ t of the topological charge defined either by the index of overlap Dirac operator or a gluonic operator is investigated at several values of temperature T (> T c ) varying the quark mass. A strong suppression of the susceptibility is observed below a certain value of the quark mass. The relation with the restoration of U A (1) is discussed.Speaker,

Axial U(1) symmetry at high temperature in 2-flavor lattice QCD

“…The quark mass dependence of the U(1) A susceptibility at T = 220 MeV implies the restoration of U(1) A symmetry in the chiral limit, which is consistent with the predictions of [2,3]. The zero modes of the overlap Dirac spectra are closely related to the topological susceptibility, which is reported in another talk [19]. As other observables to see the restoration of U(1) A , the spatial isovector meson correlators from the same gauge configuration are investigated in Ref.…”

Axial U(1) symmetry, topology, and Dirac spectra at high temperature in Nf=2 lattice QCD

“…In these proceedings, in order to examine the U(1) A symmetry in the high-temperature phase above T c , we show the results of the U(1) A susceptibility, topological susceptibility, and corresponding Dirac spectra from N f = 2 lattice QCD simulations, where finer lattice spacing, 1/a = 2.64 GeV (a ∼ 0.075 fm), than the previous works [1,4] is used. Note that a part of the results has also been reported in previous proceedings [26,27,28].…”

Axial U(1) symmetry and mesonic correlators at high temperature in $N_f=2$ lattice QCD

“…The physical quark mass (as the average of up and down quark masses) is estimated to be am = 0.0014(2) (3.7(5) MeV). Some of our results were already reported in previous proceedings [18,19,20,21].…”