D -> \pi l \nu and D -> K l \nu form factors with Nf=2+1+1 Twisted fermions

Understand

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 4-momentum transfer are f+(D -> \pi)(0) = 0.610 (23) and f+(D -> K)(0) = 0.747 (22), where the uncertainties are only statistical.