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arXiv · 0911.0472

SU(2) chiral fits to light pseudoscalar masses and decay constants

A. Bazavov·C. Bernard·C. DeTar·X. Du·W. Freeman·Steven Gottlieb·Urs M. Heller·J. E. Hetrick·J. Laiho·L. Levkova·M. B. Oktay·J. Osborn·R. Sugar·D. Toussaint·R. S. Van de Water
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Abstract

We present the results of fits to recent asqtad data in the light pseudoscalar sector using SU(2) partially-quenched staggered chiral perturbation theory. Superfine (a~0.06 fm) and ultrafine (a~0.045 fm) ensembles are used, where light sea quark masses and taste splittings are small compared to the strange quark mass. Our fits include continuum NNLO chiral logarithms and analytic terms. We give preliminary results for the pion decay constant, SU(2) low-energy constants and the chiral condensate in the two-flavor chiral limit.

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A. Bazavov, C. Bernard, C. DeTar, X. Du, W. Freeman, Steven Gottlieb, Urs M. Heller, J. E. Hetrick, J. Laiho, L. Levkova, M. B. Oktay, J. Osborn, R. Sugar, D. Toussaint, R. S. Van de Water. 2009-11-03. SU(2) chiral fits to light pseudoscalar masses and decay constants. https://arxiv.org/abs/0911.0472

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