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arXiv · hep-lat/0206011

I=2 Pion Scattering Length with the Wilson Fermion

JLQCD Collaboration·S. Aoki·M. Fukugita·S. Hashimoto·K-I. Ishikawa·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneko·Y. Kuramashi·M. Okawa·T. Onogi·S. Tominaga·N. Tsutsui·A. Ukawa·N. Yamada·T. Yoshié
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Abstract

The calculation of the I=2 pion scattering length in quenched lattice QCD is revisited. The calculation is carried out with the Wilson fermion action employing Lüscher's finite size scaling method at $β=5.9$, 6.1, and 6.3 corresponding to the range of lattice spacing $a\simeq 0.12 - 0.07$ fm. We obtain in the continuum limit $a_0m_π= -0.0410(69)$, which is consistent with the prediction of chiral perturbation theory $a_0m_π=-0.0444(10)$.

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JLQCD Collaboration, S. Aoki, M. Fukugita, S. Hashimoto, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneko, Y. Kuramashi, M. Okawa, T. Onogi, S. Tominaga, N. Tsutsui, A. Ukawa, N. Yamada, T. Yoshié. 2002-09-18. I=2 Pion Scattering Length with the Wilson Fermion. https://doi.org/10.1103/physrevd.66.077501

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