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arXiv · 1705.10906

Topological susceptibility of QCD with dynamical Möbius domain wall fermions

S. Aoki·G. Cossu·H. Fukaya·S. Hashimoto·T. Kaneko
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Abstract

We compute the topological susceptibility $χ_t$ of lattice QCD with $2+1$ dynamical quark flavors described by the Möbius domain wall fermion. Violation of chiral symmetry as measured by the residual mass is kept at $\sim$1 MeV or smaller. We measure the fluctuation of the topological charge density in a `slab' sub-volume of the simulated lattice using the method proposed by Bietenholz {\it et al.} The quark mass dependence of $χ_t$ is consistent with the prediction of chiral perturbation theory, from which the chiral condensate is extracted as $Σ^{\overline{\rm MS}} (\mbox{2GeV}) = [274(13)(29)\mbox{MeV}]^3$, where the first error is statistical and the second one is systematic. Combining the results for the pion mass $M_π$ and decay constant $F_π$, we obtain $χ_t = 0.229(03)(13)M_π^2F_π^2$ at the physical point.

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S. Aoki, G. Cossu, H. Fukaya, S. Hashimoto, T. Kaneko. 2018-11-29. Topological susceptibility of QCD with dynamical Möbius domain wall fermions. https://doi.org/10.1093/ptep%2Fpty041

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