相关论文: Lattice Determination of the $B^\ast B \pi$ Coupli…
The coupling $g_{B^\ast B \pi}$ is related to the form factor at zero momentum of the axial current between $B^\ast$- and $B$-states. This form factor is evaluated on the lattice using static heavy quarks and light quark propagators…
The $B^* B\pi$ coupling is a fundamental parameter of chiral effective Lagrangian with heavy-light mesons and can constrain the chiral behavior of $f_B$, $B_B$ and the $B\to \pi l \nu$ form factor in the soft pion limit. We compute the $B^*…
We report on a calculation of the $B^*B\pi$ coupling in lattice QCD. The strong matrix element $\langle B \pi | B^*\rangle$ is directly related to the leading order low-energy constant in heavy meson chiral perturbation theory (HM$\chi$PT)…
The static $B^{*}B\pi$ coupling, $\hat{g}_\chi$, a low energy constant in the leading order heavy meson chiral Lagrangian, is determined using $N_\mathrm{f} = 2$ lattice QCD. We use CLS ensembles with lattice spacings and pion masses down…
We study an accurate method for the lattice calculation of the B*Bpi Coupling in the static limit, paying particular attention to excited state contamination. As this coupling is a parameter of the heavy meson chiral Lagrangian, it is…
The B* B pi coupling is a fundamental parameter of chiral effective Lagrangian with heavy-light mesons and can constrain the B->pi l nu form factor in the soft pion limit which will be useful for precise determination of |Vub|. We compute…
We report on a calculation of the B*Bpi coupling in lattice QCD. The strong matrix element for a B* to Bpi transition is directly related to the leading order low-energy constant in heavy meson chiral perturbation theory (HMChPT) for B…
According to heavy-meson chiral perturbation theory, the vector form factor $f_+(q^2)$ of exclusive semi-leptonic decay $B\to \pi \ell \nu$ is closely related, at least in the soft-pion region (i.e., $q^{2} \sim (m_B-m_{\pi})^2$), to the…
We present two-flavor lattice QCD estimates of the hadronic couplings $g_{B^*_0 B \pi}$ and $g_{B_1^* B_0^* \pi}$ that parametrise the non leptonic decays $B^*_0 \to B \pi$ and $B^*_1 \to B_0^* \pi$. We use CLS two-flavour gauge ensembles.…
By means of QCD simulations on the lattice, we compute the coupling of the heavy-light mesons to a soft pion in the static heavy quark limit. The gauge field configurations used in this calculations include the effect of N_f=2 dynamical…
We explore the transitions B$(0^+)$ to B $\pi$ and B$_s(0^+)$ to B K from lattice QCD with $N_f=2$ flavours of sea quark, using the static approximation for the heavy quark. We evaluate the effective coupling constants, predicting a…
The determinations of $|V_{\rm ub}|$ from the exclusive branching ratios of $B\to \tau \nu$ and $B \to \pi l \nu$ tend to show a tension at the level of $3\sigma$ \cite{Beringer:1900zz}. On the theoretical side they depend on the lattice…
The exclusive semileptonic decay $B \rightarrow \pi \ell \nu$ is a key process for the determination of the Cabibbo-Kobayashi-Maskawa matrix element $V_{ub}$ from the comparison of experimental rates as a function of $q^2$ with…
We present an exploratory lattice study of $B\to\pi$ semileptonic decay form factors using the nonrelativistic lattice QCD for heavy quark with Wilson light quark on a $16^3 \times 32$ quenched lattice at $\beta=5.8$. The matrix elements…
We consider three-flavor QCD and perform a determination of the low-energy coupling $\hat{g}_\chi$ of SU(2) Heavy Meson Chiral Perturbation Theory. It is the $B^*B\pi$ coupling in the limit of static heavy and chiral light quarks and has…
We present results of a lattice study of the form factors in the decay B-> pi l nu. We attempt to disentangle the the dependence of the form factors on the light quark masses and the momentum transfer. Using models of the q^2 dependence we…
We present a first $N_{\rm f}=2$ lattice estimate of the hadronic coupling $g_{12}$ which parametrizes the strong decay of a radially excited $B^*$ meson into the ground state $B$ meson at zero recoil. We work in the static limit of Heavy…
We present the results of a quenched lattice QCD study of the coupling g_hat, in the static heavy quark limit. After combining this with our previous results obtained by using propagating heavy quarks with a mass around the physical charm…
We discuss the main issues in dealing with heavy quarks on the lattice and shortly present the different approaches used. We discuss a selection of computations covering first the b-quark mass and the B(s) meson decay constants as the…
We calculate the axial couplings of mesons and baryons containing a heavy quark in the static limit using lattice QCD. These couplings determine the leading interactions in heavy hadron chiral perturbation theory and are central quantities…