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arXiv · 0911.2534

Staggered chiral perturbation theory in the two-flavor case

Xining Du
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Abstract

I study two-flavor staggered chiral perturbation theory in the light pseudoscalar sector. The pion mass and decay constant are calculated through NLO in the partially-quenched case. In the limit where the strange quark mass is large compared to the light quark masses and the taste splittings, I show that the SU(2) staggered chiral theory emerges from the SU(3) staggered chiral theory, as expected. Explicit relations between SU(2) and SU(3) low energy constants and taste-violating parameters are given. The results are useful for SU(2) chiral fits to asqtad data and allow one to incorporate effects from varying strange quark masses.

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BibTeXRIS

Xining Du. 2010-11-08. Staggered chiral perturbation theory in the two-flavor case. https://doi.org/10.1103/physrevd.82.014016

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