Article

Charmed-Meson Decay Constants in Three-Flavor Lattice QCD

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Department of Physics, Columbia University, New York, New York, United States
(Impact Factor: 7.73). 10/2005; 95(12):122002. DOI: 10.1103/PhysRevLett.95.122002
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ABSTRACT We present the first lattice QCD calculation with realistic sea quark content of the ${D}^{+}$-meson decay constant ${f}_{{D}^{+}}$. We use the MILC Collaboration's publicly available ensembles of lattice gauge fields, which have a quark sea with two flavors (up and down) much lighter than a third (strange). We obtain ${f}_{{D}^{+}}=201\ifmmode\pm\else\textpm\fi{}3\ifmmode\pm\else\textpm\fi{}17\text{ }\text{ }\mathrm{MeV}$, where the errors are statistical and a combination of systematic errors. We also obtain ${f}_{{D}_{s}}=249\ifmmode\pm\else\textpm\fi{}3\ifmmode\pm\else\textpm\fi{}16\text{ }\text{ }\mathrm{MeV}$ for the ${D}_{s}$ meson.

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