Light quark masses and pseudoscalar decay constants from Nf=2 Lattice QCD with twisted mass fermions
Abstract
We present the results of a lattice QCD calculation of the average up-down and strange quark masses and of the light meson pseudoscalar decay constants with Nf=2 dynamical fermions. The simulation is carried out at a single value of the lattice spacing with the twisted mass fermionic action at maximal twist, which guarantees automatic O(a)-improvement of the physical quantities. Quark masses are renormalized by implementing the non-perturbative RI-MOM renormalization procedure. Our results for the light quark masses are m_ud^{msbar}(2 GeV)= 3.85 +- 0.12 +- 0.40 MeV, m_s^{msbar}(2 GeV) = 105 +- 3 +- 9 MeV and m_s/m_ud = 27.3 +- 0.3 +- 1.2. We also obtain fK = 161.7 +- 1.2 +- 3.1 MeV and the ratio fK/fpi=1.227 +- 0.009 +- 0.024. From this ratio, by using the experimental determination of Gamma(K-> mu nu (gamma))/Gamma(pi -> mu nu (gamma)) and the average value of |Vud| from nuclear beta decays, we obtain |Vus|=0.2192(5)(45), in agreement with the determination from Kl3 decays and the unitarity constraint.
Keywords
Cite
@article{arxiv.0709.4574,
title = {Light quark masses and pseudoscalar decay constants from Nf=2 Lattice QCD with twisted mass fermions},
author = {B. Blossier and Ph. Boucaud and P. Dimopoulos and F. Farchioni and R. Frezzotti and V. Gimenez and G. Herdoiza and K. Jansen and V. Lubicz and C. Michael and D. Palao and M. Papinutto and A. Shindler and S. Simula and C. Tarantino and C. Urbach and U. Wenger and ETM Collaboration},
journal= {arXiv preprint arXiv:0709.4574},
year = {2010}
}
Comments
20 pages, 5 figures