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Lattice calculation of low energy constants with Ginsparg-Wilson type fermions

Christof Gattringer·Philipp Huber·C. B. Lang
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Abstract

We present a quenched lattice calculation of low energy constants using the chirally improved Dirac operator. Several lattice sizes at different lattice spacings are studied. We systematically compare various methods for computing these quantities, using pseudoscalar and axial vector correlators. We find consistent results for the different approaches, giving rise to f_π= 96(2)(4) MeV, f_K = 106(1)(8) MeV, f_K/f_π=1.11(1)(2), Sigma= -(286(4)(31) MeV)^3, the average light quark mass m = 4.1(2.4) MeV and m_s = 101(8) MeV.

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Christof Gattringer, Philipp Huber, C. B. Lang. 2005-11-08. Lattice calculation of low energy constants with Ginsparg-Wilson type fermions. https://doi.org/10.1103/physrevd.72.094510

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