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arXiv · hep-lat/0509190

Double poles in Lattice QCD with mixed actions

Maarten Golterman·Taku Izubuchi·Yigal Shamir
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Abstract

We consider effects resulting from the use of different discretizations for the valence and the sea quarks, considering Wilson and/or Ginsparg--Wilson fermions. We assume that such effects appear through scaling violations that can be studied using effective-lagrangian techniques. We show that a double pole is present in flavor-neutral Goldstone meson propagators, even if the flavor non-diagonal Goldstone mesons made out of valence or sea quark have equal masses. We then consider some observables known to be anomalously sensitive to the presence of a double pole. We find that the double-pole enhanced scaling violations may turn out to be rather small in practice.

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Maarten Golterman, Taku Izubuchi, Yigal Shamir. 2005-09-30. Double poles in Lattice QCD with mixed actions. https://doi.org/10.1016/j.nuclphysbps.2006.01.020

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