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arXiv · 1012.0200

Pseudoscalar decay constants from N_f=2+1+1 twisted mass lattice QCD

Federico Farchioni·Gregorio Herdoiza·Karl Jansen·Marcus Petschlies·Carsten Urbach·ETM collaboration
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Abstract

We present first results for the pseudoscalar decay constants $f_K$, $f_D$ and $f_{D_s}$ from lattice QCD with N_f=2+1+1 flavours of dynamical quarks. The lattice simulations have been performed by the European Twisted Mass collaboration (ETMC) using maximally twisted mass quarks. For the pseudoscalar decay constants we follow a mixed action approach by using so called Osterwalder-Seiler fermions in the valence sector for strange and charm quarks. The data for two values of the lattice spacing and several values of the up/down quark mass is analysed using chiral perturbation theory.

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Federico Farchioni, Gregorio Herdoiza, Karl Jansen, Marcus Petschlies, Carsten Urbach, ETM collaboration. 2010-12-01. Pseudoscalar decay constants from N_f=2+1+1 twisted mass lattice QCD. https://arxiv.org/abs/1012.0200

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