Related papers: B -> D* l nu at zero recoil: an update
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 update the lattice calculation of the $B\to\pi$ semileptonic form factors, which have important applications to the CKM matrix element $|V_{ub}|$ and the $B\to\pi\ell^+\ell^-$ rare decay. We use MILC asqtad ensembles with $N_f=2+1$ sea…
Semileptonic $B_{(s)}$ decays are of great phenomenological interest because they allow to determine e.g. CKM matrix elements or test lepton flavor universality. Taking advantage of already existing lattice data, we demonstrate the analysis…
The h+, h_A1 form factors for the semi-leptonic B->D and B->D* decays are evaluated in quenched lattice QCD with beta=6.2. The action and the operators are fully O(a) non-perturbatively improved. The Isgur-Wise function is evaluated and…
Short description of our calculation of the form factor needed to determine CKM element |V_{cb}| from the exclusive decay B -> D^*l\nu. For full details, see hep-ph/0110253. Also, here we recommend distribution for CKM fits.
Using $(2+1)$-flavor lattice QCD, we compute the 10 form factors describing the $\Lambda_b \to \Lambda$ matrix elements of the $b \to s$ vector, axial vector, and tensor currents. The calculation is based on gauge field ensembles generated…
This paper gives a brief review on the recent lattice QCD calculations of the B to K/K*l+l- semi-leptonic decay form factors.
We give a progress report on the calculation of B meson mixing matrix elements, focusing on contributions that could arise beyond the Standard Model. The calculation uses asqtad (light quark) and Fermilab (heavy quark) valence actions and…
The computation of the form factors for the $B_s \to K \ell \nu$ decay is presented. The b quark is treated by means of Heavy Quark Effective Theory, currently in the static approximation. In these proceedings we discuss the extraction of…
We present recent progress in calculating the semileptonic form factors $h_{A_1}(w)$ for the $\bar{B} \to D^{\ast} \ell \bar{\nu}$ decays. We use the Oktay-Kronfeld (OK) action for the charm and bottom valence quarks and the HISQ action for…
We present lattice results for the vector and scalar form factors of the semileptonic decays D -> \pi \ell \nu_ell and D -> K \ell \nu_\ell in the physical range of values of squared four momentum transfer q^2, obtained with N_f=2 maximally…
We compute the vector, scalar, and tensor form factors for the $B\to \pi$, $B\to K$, and $B_s\to K$ amplitudes, which are needed to describe semileptonic $B$-meson decay rates for both the charged and neutral current cases. We use the…
We propose a strategy to compute form factors entering the semileptonic decay channel of $B$ mesons into orbitally excited (P wave) $D^{**}$ charmed mesons on the lattice using, for the first time, realistic charm quarks having a finite…
Precise theoretical predictions derived from the Standard Model are a key ingredient in searches for new physics in the flavor sector. The large mass and long lifetime of the $b$ quark make processes involving $b$ quarks of particular…
We present an updated determination of the values of $\vert V_{cb} \vert$, $R(D^*)$ and $\vert V_{ub} \vert/\vert V_{cb} \vert$ based on the new data on semileptonic $B \to D^* \ell \nu_\ell$ decays by the Belle and Belle-II Collaborations…
We report a measurement of the branching ratio B(D+-->rho^0 l nu)/ B(D+-->K*0 l nu) from the Fermilab charm hadroproduction experiment E791. Based on signals of 49+-17 events in the D+--> rho^0 e nu mode and 54+-18 events in the D+--> rho^0…
We present a study of the $D$ and $B$ leptonic decay constants on the MILC $N_f=2+1$ asqtad gauge ensembles using asqtad-improved staggered light quarks and clover heavy quarks in the Fermilab interpretation. Our previous analysis…
Using a fully relativistic lattice fermion action, we compute the form factors of the semileptonic decay $B\to\pi\ell\nu$, which is required for the determination of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{ub}|$. We employ the…
We present results for form factors of semileptonic decays of $D$ and $B$ mesons in 2+1 flavor lattice QCD using the MILC gauge configurations. With an improved staggered action for light quarks, we successfully reduce the systematic error…
Theoretical and computational advances in lattice calculations are reviewed, with focus on examples relevant to the unitarity triangle of the CKM matrix. Recent progress in semi-leptonic form factors for B -> pi l nu and B -> D* l nu, as…