Related papers: Width difference in the $B_s$-$\bar{B}_s$ system w…
We present a perturbative calculation of the renormalization constants for the $\Delta B=2$ four-quark operators, which is needed to evaluate the bag parameters $B_B$ and $B_S$ in lattice QCD. The one-loop coefficients are calculated for…
We compute several matrix elements of dimension-six four-fermion operators and extract their B-parameters. The calculations have been performed with the tree-level Clover action at $\beta = 6.0$. The renormalization constants and mixing…
We report on the advances in our unquenched calculation of the matrix elements relevant for the analysis of B^0-\bar B^0 mixing using the Asqtad (light quark) and Fermilab (heavy quark) actions. We have calculated the hadronic parameters…
We present a two-flavor QCD calculation of $B_K$ on a $16^3 \times 32$ lattice at $a\sim 0.12$ fm (or equivalently $a^{-1}\sim$1.67 GeV). Both valence and sea quarks are described by the overlap fermion formulation. The matching factor is…
We compute the QCD corrections to the decay rate difference in the $B_s-\bar B_s$ system, $\Delta\Gamma_{B_s}$, in the next-to-leading logarithmic approximation using the heavy quark expansion approach. Going beyond leading order in QCD is…
The present status of the theoretical estimates of the difference between the widths of the neutral Bs-mesons and of the B-meson lifetime ratios is reviewed. In particular, the lattice results for the matrix elements of the relevant (delta…
A lattice QCD calculation of the kaon $B$ parameter $B_K$ is carried out with the Wilson quark action in the quenched approximation at $\beta=6/g^2=5.9-6.5$. The mixing problem of the $\Delta s=2$ four-quark operators is solved…
We calculate the mass difference between the $\Upsilon$ and $\eta_b$ and the $\Upsilon$ leptonic width from lattice QCD using the Highly Improved Staggered Quark formalism for the $b$ quark and including $u$, $d$, $s$ and $c$ quarks in the…
We give results for the Upsilon spectrum from lattice QCD using an improved version of the NRQCD action for b quarks which includes radiative corrections to kinetic terms at O(v^4) in the velocity expansion. We also include for the first…
We report on lattice calculations of the $B$ meson decay constant and the B-parameters using the NRQCD action for heavy quark. We performed a set of calculations at three lattice spacings in the quenched approximation in order to…
We compute the ratio $\Lambda_L/\Lambda_{\bar{MS}}$ between the scale parameter $\Lambda_L$, associated with a lattice formulation of QCD using the overlap-Dirac operator, and $\Lambda_{\bar{MS}}$ of the $\bar{\rm MS}$ renormalization…
We explore the effect of higher order operators in the non-relativistic formulation of QCD (NRQCD). We calculated masses in the b \bar b spectrum using quenched gauge configurations at beta = 6.0 and two different NRQCD actions which have…
We present a calculation of the hindered M$1$ $\Upsilon(2S) \to \eta_b(1S) \gamma$ decay rate using lattice non-relativistic QCD. The calculation includes spin-dependent relativistic corrections to the NRQCD action through…
We study the $B^0_s-\bar{B^0_s}$ mixing amplitude in Standard Model by computing the relevant hadronic matrix element in the static limit of lattice HQET with the Neuberger light quark action. In the quenched approximation, and after…
We report progress on calculating the $K_L$-$K_S$ mass difference in lattice QCD. T he calculation is performed on a 2+1 flavor, domain wall fermion, $16^3\times 32$ en semble with a 421 MeV pion mass. We include only current-current…
We update the Standard-Model predictions for several quantities related to $B_s - \bar B_s$ and $B_d - \bar B_d$ mixing. The mass and width differences in the $B_s$ system read $ \Delta M_s^{\rm SM} = (17.3 \pm 2.6) ps^{-1}$ and $\Delta…
The computation on the lattice of the bag parameter $B_{B_s}$ associated to the $B_s - \bar{B_s}$ mixing amplitude in the Standard Model is presented. The estimation has been made by combining the static limit of HQET and the Neuberger…
We perform a lattice study of heavy baryons, containing one ($\Lambda_b$) or two $b$-quarks ($\Xi_b$). Using the quenched approximation we obtain for the mass of $\Lambda_b$ $$ M_{\Lambda_b}= 5.728 \pm 0.144 \pm 0.018 {\rm GeV}.$$ The mass…
By combining the first unquenched lattice computation of the B-meson binding energy and the two-loop contribution to the lattice HQET residual mass, we determine the (\bar{{MS}}) (b)-quark mass, (\bar{m}_{b}(\bar{m}_{b})). The inclusion of…
We discuss recent results on the excitation spectra of B and D-mesons obtained in the framework of non-relativistic lattice QCD in the quenched approximation. The results allow for the determination of the $\msbar$-mass of…