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arXiv · 1311.3080

Pseudoscalar decay constants $f_K/f_\pi$, $f_D$ and $f_{D_s}$ with $N_f = 2 + 1 + 1$ ETMC configurations

P. Dimopoulos·R. Frezzotti·P. Lami·V. Lubicz·E. Picca·L. Riggio·G. C. Rossi·F. Sanfilippo·S. Simula·C. Tarantino
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Abstract

We present a lattice QCD calculation of the pseudoscalar decay constants $f_K$, $f_D$ and $f_{D_s}$ performed by the European Twisted Mass Collaboration with $N_f = 2 + 1 + 1$ dynamical fermions. We simulated at three different values of the lattice spacing, the smallest being approximately $0.06fm$, and with pion masses as small as $210$MeV. Our main results are: $f_{K^+}/f_{\pi^+}=1.183(17)$, $f_{K^+}=154.4(2.1)$MeV, $f_{D_s}=242.1(8.3)$MeV, $f_D=201.9(8.0)$MeV, $f_{D_s}/f_D=1.199(25)$ and $(f_{D_s}/f_D) / (f_K/f_\pi) = 1.005(15)$.

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P. Dimopoulos, R. Frezzotti, P. Lami, V. Lubicz, E. Picca, L. Riggio, G. C. Rossi, F. Sanfilippo, S. Simula, C. Tarantino. 2013-11-13. Pseudoscalar decay constants $f_K/f_\pi$, $f_D$ and $f_{D_s}$ with $N_f = 2 + 1 + 1$ ETMC configurations. https://arxiv.org/abs/1311.3080

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