1081 articles – 5292 Notices  [english version]
 HAL : in2p3-00116766, version 1
 arXiv : hep-ph/0606167
 Journal of High Energy Physics 10 (2006) 081
 The Unitarity Triangle Fit in the Standard Model and Hadronic Parameters from Lattice QCD: A Reappraisal after the Measurements of $\Delta m_s$ and $BR(B \to \tau \nu_{\tau)}$
 UTfit Collaboration(s)
 (2006)
 The recent measurements of the B_s meson mixing amplitude by CDF and of the leptonic branching fraction BR(B to tau nu) by Belle call for an upgraded analysis of the Unitarity Triangle in the Standard Model. Besides improving the previous constraints on the parameters of the CKM matrix, these new measurements, combined with the recent determinations of the angles alpha, beta and gamma from non-leptonic decays, allow, in the Standard Model, a quite accurate extraction of the values of the hadronic matrix elements relevant for K-Kbar and B_{s,d}-B_{s,d}bar mixing and of the leptonic decay constant f_B. These values, obtained "experimentally'', can then be compared with the theoretical predictions, mainly from lattice QCD. In this paper we upgrade the UT fit, we determine from the data the kaon B-parameter B_Khat, the B^0 mixing amplitude parameters f_Bs B^{1/2}_Bs and xi, the decay constant f_B, and make a comparison of the obtained values with lattice predictions. We also discuss the different determinations of V_ub and show that current data do not favour the value measured in inclusive decays.
 Thème(s) : Physique/Physique des Hautes Energies - Phénoménologie
 Lien vers le texte intégral : http://fr.arXiv.org/abs/hep-ph/0606167
 in2p3-00116766, version 1 http://hal.in2p3.fr/in2p3-00116766 oai:hal.in2p3.fr:in2p3-00116766 Contributeur : Nicole Berger <> Soumis le : Lundi 27 Novembre 2006, 17:40:30 Dernière modification le : Vendredi 2 Février 2007, 17:12:14