D > \pi l \nu and D > K l \nu form factors with Nf=2+1+1 Twisted fermions
Abstract
We present a lattice QCD determination of the vector and scalar form factors of the semileptonic decays D>\pi l \nu and D > K l \nu which are relevant for the extraction of the CKM matrix elements Vcd and Vcs from experimental data. Our analysis is based on the gauge configurations produced by the European Twisted Mass Collaboration with Nf = 2+1+1 dynamical fermions. We simulated at three different values of the lattice spacing and with pion masses as small as 210 MeV. Our preliminary estimates for the vector form factor at zero 4momentum transfer are f+(D > \pi)(0) = 0.610 (23) and f+(D > K)(0) = 0.747 (22), where the uncertainties are only statistical. By combining our results with the experimental values of f+(D > \pi)(0) Vcd and f+(D > K)(0) Vcs we obtain Vcd = 0.2336 (93) and Vcs = 0.975 (30), which together with the PDG determination of Vcb are in agreement with the unitarity constraint of the Standard Model.
 Publication:

arXiv eprints
 Pub Date:
 November 2015
 arXiv:
 arXiv:1511.04877
 Bibcode:
 2015arXiv151104877C
 Keywords:

 High Energy Physics  Lattice;
 High Energy Physics  Phenomenology
 EPrint:
 7 pages, 4 figures, to appear in Proc. of the XXXIII Int'l Symposium on Lattice Field Theory, 1418 July 2015, Kobe (Japan)