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arXiv · hep-ph/0306299

Precision computation of the leptonic D_s-meson decay constant in quenched QCD

Abstract

We summarize a computation of the leptonic decay constant f_D_s of the D_s-meson in quenched QCD on the lattice. We perform a direct simulation at the masses of the strange and the charm quarks at four different lattice spacings from approximately 0.1 fm to 0.05 fm. Fully non perturbative O(a)-improvement is employed. After taking the continuum limit we arrive at a value of f_D_s=252(9) MeV, when setting the scale with the Kaon decay constant f_K=160 MeV. Setting the scale with the nucleon mass instead leads to a decrease of about 20 MeV of f_D_s.

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Andreas Juttner, Juri Rolf. 2003-06-30. Precision computation of the leptonic D_s-meson decay constant in quenched QCD. https://arxiv.org/abs/hep-ph/0306299

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