相关论文: Precision for B-meson matrix elements

We review the current status of theoretical predictions for mixing quantities and lifetimes in the $B$-sector. In particular, due to the first non-zero measurement of the decay rate difference in the neutral $B_s$-system, $\Delta \Gamma_s/…

We systematically compute the $\Lambda_b(p, s_b) \to \Lambda_c(2595)^+$ and $\Lambda_b(p, s_b) \to \Lambda_c(2625)^+$ form factors within the Heavy Quark Effective Theory (HQET) framework including $\mathcal{O}(1/m_c^2)$. Besides taking…

We present a precise lattice computation of pseudoscalar and vector heavy-light meson masses for heavy-quark masses ranging from the physical charm mass up to $\simeq 4$ times the physical b-quark mass. We employ the gauge configurations…

We consider QCD with one massless quark and one heavy quark in a finite volume of linear extent L_0 ~ 0.2 fm. In this situation, HQET represents an expansion in terms of 1/z=1/(m L_0), which we test by a non-perturbative computation of…

The ratio of the top-quark branching fractions R = B(t to Wb)/B(t to Wq), where the denominator includes the sum over all down-type quarks (q = b, s, d), is measured in the t t-bar dilepton final state with proton-proton collision data at…

We study the heavy quark mass dependence of selected observables constructed from heavy-light meson correlation functions in small-volume two-flavour lattice QCD after taking the continuum limit. The light quark mass is tuned to zero,…

Using heavy meson chiral perturbation theory, we consider the light quark-mass and spatial volume dependence of the matrix elements of \Delta B=2 and \Delta C=2 four-quark operators relevant for B^{0}_{(s)}{-}\bar{B}^{0}_{(s)} and…

We present an update of the Fermilab Lattice and MILC Collaborations project to compute the form factors for semileptonic $B_{(s)}$-meson decays. Our calculation uses the highly improved staggered quark (HISQ) action for sea and valence…

We present updates from QCDSF/UKQCD/CSSM on the $SU(3)_f$ breaking in $B$ meson decay constants. The $b$-quarks are generated with an anisotropic clover-improved action, and are tuned to match properties of the physical $B$ and $B^*$…

We present a measurement of the ratio of top quark branching fractions R = B(t -> Wb)/B(t -> Wq), where q can be a d, s or b quark, in the lepton+jets and dilepton ttbar final states. The measurement uses data from 5.4 fb-1 of ppbar…

We carry out a thorough analysis with the GEVP method to obtain ground-state and first-excited-state masses and decay constants of bottom-strange (pseudo-scalar and vector) mesons. This computation is done for quenched, nonperturbatively…

We present a fit to measured moments of inclusive distributions in B->Xc lv and B-> Xs gamma decays to extract values for the CKM matrix element |Vcb|, the b- and c-quark masses, and higher order parameters that appear in the Heavy Quark…

We present an update of our lattice QCD determination of the $B_c\to J/\psi$ vector and axial-vector form factors, including new results for the tensor form factors. We use the Highly Improved Staggered Quark action for all valence quarks,…

We explore a possibility of optimization of the method of determination of the top quark mass from $M_{b\ell}$ distribution in semi-leptonic decays $t \to b \ell\nu$ at LHC and a future linear collider (LC). We discover that the systematic…

By combining the first unquenched lattice computation of the B-meson binding energy with the recently calculated two-loop contribution to the lattice HQET mass, we determine the $\bar{MS}$ b-quark mass, $\bar{m}_{b}(\bar{m}_{b})$ at the…

We report on the precision determination of the top-quark mass to next-to-next-to-leading order in QCD in well-defined renormalization schemes using data from the Large Hadron Collider for single-top and top-quark pair production. We also…

The determination of quark masses has been transformed in the past few years by accurate results from realistic lattice QCD. This has meant a range of new methods for both b and c quarks which I will describe along with results from…

We perform a benchmark study of the step scaling procedure for the ratios of renormalization constants extracted from position space correlation functions. We work in the quenched approximation and consider the pseudoscalar, scalar, vector…

Lightcone distribution amplitudes (LCDAs) of heavy meson within heavy quark effective theory (HQET) are crucial for predicting physical observables in $B$ decays, but unfortunately there is no first-principle result due to severe…

We study effective energies of heavy-light meson correlation functions in lattice QCD and a small volume of (0.2 fm)^4 to non-perturbatively calculate their dependence on the heavy quark mass in the continuum limit. Our quenched results…