Scaling behavior and sea quark dependence of pion spectrum with HYP-smeared staggered fermions

Source: arXiv

ABSTRACT We study the pion spectrum (and in particular taste-symmetry breaking within it) using HYP-smeared valence staggered fermions on the coarse and fine MILC lattices (which have asqtad staggered sea quarks). We focus on the dependence on lattice spacing and sea-quark mass. We also update our results on source dependence. Our main conclusion is that on the MILC fine lattices the appropriate power-counting for SU(3) staggered chiral perturbation theory may have discretization errors entering at next-to-leading order rather than at leading-order. Comment: 7 pages, 8 figures, Lattice 2008 proceeding

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