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arXiv · 1111.3729

SU(2) chiral perturbation theory low-energy constants from staggered 2+1 flavor simulations

Enno E. Scholz·Szabolcs Borsanyi·Stephan Durr·Zoltan Fodor·Sandor D. Katz·Stefan Krieg·Andreas Schafer·Kalman K. Szabo
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Abstract

We measure the pion mass and decay constant on ensembles generated by the Wuppertal-Budapest Collaboration, and extract the NLO low-energy constants l_3 and l_4 of SU(2) chiral perturbation theory. The data are generated in 2+1 flavor simulations with Symanzik glue and 2-fold stout-smeared staggered fermions, with pion masses varying from 135 MeV to 400 MeV, lattice scales between 0.7 GeV and 2.0 GeV, and m_s kept at its physical value. Furthermore, by excluding the lightest mass points, we are able to test the reliability of SU(2) chPT as a tool to extrapolate towards the physical point from higher pion masses.

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Enno E. Scholz, Szabolcs Borsanyi, Stephan Durr, Zoltan Fodor, Sandor D. Katz, Stefan Krieg, Andreas Schafer, Kalman K. Szabo. 2011-11-16. SU(2) chiral perturbation theory low-energy constants from staggered 2+1 flavor simulations. https://arxiv.org/abs/1111.3729

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