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arXiv · 1112.5259

Kaon semileptonic form factors in QCD with exact chiral symmetry

JLQCD Collaboration·T. Kaneko·S. Aoki·G. Cossu·X. Feng·H. Fukaya·S. Hashimoto·J. Noaki·T. Onogi
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Abstract

We report on our calculation of the kaon semileptonic form factors in Nf=2+1 lattice QCD. Chiral symmetry is exactly preserved by using the overlap quark action for a straightforward comparison with chiral perturbation theory (ChPT). We simulate three pion masses down to 290 MeV at a single lattice spacing of 0.11 fm and at a strange quark mass very close to its physical value. The form factors near zero momentum transfer are precisely calculated by using the all-to-all propagator and twisted boundary conditions. We compare the normalizations and slopes of the form factors with ChPT and experiments.

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JLQCD Collaboration, T. Kaneko, S. Aoki, G. Cossu, X. Feng, H. Fukaya, S. Hashimoto, J. Noaki, T. Onogi. 2011-12-22. Kaon semileptonic form factors in QCD with exact chiral symmetry. https://arxiv.org/abs/1112.5259

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