The decay constants fD{\mathbf{f_D}} and fDs{\mathbf{f_{D_{s}}}} in the continuum limit of Nf=2+1{\mathbf{N_f=2+1}} domain wall lattice QCD

We present results for the decay constants of the $D$ and $D_s$ mesons computed in lattice QCD with $N_f=2+1$ dynamical flavours. The simulations are based on RBC/UKQCD's domain wall ensembles with both physical and unphysical light-quark masses and lattice spacings in the range 0.11--0.07$\,$fm. We employ the domain wall discretisation for all valence quarks. The results in the continuum limit are $f_D=208.7(2.8)_\mathrm{stat}\left(^{+2.1}_{-1.8}\right)_\mathrm{sys}\,\mathrm{MeV}$ and $f_{D_{s}}=246.4(1.3)_\mathrm{stat}\left(^{+1.3}_{-1.9}\right)_\mathrm{sys}\,\mathrm{MeV}$ and $f_{D_s}/f_D=1.1667(77)_\mathrm{stat}\left(^{+57}_{-43}\right)_\mathrm{sys}$. Using these results in a Standard Model analysis we compute the predictions $|V_{cd}|=0.2185(50)_\mathrm{exp}\left(^{+35}_{-37}\right)_\mathrm{lat}$ and $|V_{cs}|=1.011(16)_\mathrm{exp}\left(^{+4}_{-9}\right)_\mathrm{lat}$ for the CKM matrix elements

Vus and lepton universality from kaon decays with the KLOE detector

KLOE has measured most decay branching ratios of Ks, Kl and K+/- mesons. It has also measured the Kl and the K+- lifetime and determined the shape of the form factors involved in kaon semileptonic decays. We present in the following a description of the above measurements and a well organized compendium of all of our data, with particular attention to correlations. These data provide the basis for the determination of the CKM parameter Vus and a test of the unitarity of the quark flavor mixing matrix. We also test lepton universality and place bounds on new physics using measurements of Vus from Kl2 and Kl3 decays.Comment: 23 pages, 12 figures. Submitted to JHE

The decay constants fD and fDs in the continuum limit of N=2+1 domain wall lattice QCD

We present results for the decay constants of the D and D s mesons computed in lattice QCD with N f = 2 + 1 dynamical flavours. The simulations are based on RBC/UKQCD’s domain wall ensembles with both physical and unphysical light-quark masses and lattice spacings in the range 0.11-0.07 fm. We employ the domain wall discretisation for all valence quarks.<br/