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Topological susceptibility in staggered fermion chiral perturbation theory

Brian Billeter·Carleton DeTar·James Osborn
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Abstract

The topological susceptibility of the vacuum in quantum chromodynamics has been simulated numerically using the Asqtad improved staggered fermion formalism. At nonzero lattice spacing the residual fermion doublers (fermion ``tastes'') in the staggered fermion formalism give contributions to the susceptibility that deviate from conventional continuum chiral perturbation theory. In this brief report we estimate the taste-breaking artifact and compare it with results of recent simulations, finding that it accounts for roughly half of the scaling violation.

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Brian Billeter, Carleton DeTar, James Osborn. 2004-06-18. Topological susceptibility in staggered fermion chiral perturbation theory. https://doi.org/10.1103/physrevd.70.077502

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