相关论文: $B\to D^\ast\ell\nu$ at non-zero recoil
We present the first lattice QCD calculation of the decay constants f_B and f_{B_s} with physical light quark masses. We use configurations generated by the MILC collaboration including the effect of u, d, s and c HISQ sea quarks at three…
The CLEO Collaboration has extracted improved values of |V_cb| and |V_ub| from measurements of exclusive and inclusive decays of B mesons. The measurement of B -> D* ell nu at zero recoil combined with the predicted form factor F_D*(w_min)…
We report on our calculation of the B \to D^(*) \ell \nu form factors in 2+1 flavor lattice QCD. The M\"obius domain-wall action is employed for light, strange, charm and bottom quarks. At lattice cutoffs 1/a \sim 2.4, 3.6 and 4.5 GeV, we…
We analyze the semileptonic rare decays of $B$ meson to $K_{1} (1270)$ and $K_{1} (1400)$ axial vector mesons. The $B\to K_{1} (1270,1400) \ell^+ \ell^-$ decays are significant flavor changing neutral current decays of the $B$ meson. These…
We study $B_c \to (D,\,D^{\ast})\,l\,\nu$ semileptonic decays mediated via $b \to u\,l\,\nu$ charged current interactions using the $B_c \to (D,\,D^{\ast})$ transition form factors obtained in the covariant light front quark model. We give…
We provide a 0.8\%-accurate determination of $V_{cs}$ from combining experimental results for the differential rate of $D \rightarrow K$ semileptonic decays with precise form factors that we determine from lattice QCD. This is the first…
According to the heavy-quark flavour symmetry, the $B\to \pi, K$ transition form factors could be related to the corresponding ones of D-meson decays near the zero recoil point. With the recent precisely measured exclusive semileptonic…
Motivated by the experiments of heavy flavor physics at running LHC and upgrading SuperKEKB/Belle-II in the future, the nonleptonic $B^{\ast}_{(s)}\to M_1 M_2$ $(M=D$, $D_s$, $\pi$, $K)$ weak decays are studied in this paper. The amplitudes…
Motivated by the rapid development of heavy flavor physics experiment, we study the tree-dominated nonleptonic $\bar{B}_{u,d,s}^* \to D_{u,d,s}^*V$~($V=D^{*-},D_s^{*-},K^{*-},{\rho}^-$) decays within the factorization approach. The relevant…
We re-examine the determination of $|V_{cb}|$ from $B\to D \ell \nu$ in view of recent experimental and theoretical progress, discussing the parameterization of the form factors and studying the role played by the unitarity constraints. Our…
We present progress on an ongoing calculation of the $B_s\to D_s^{(*)} l \nu$ form factors calculated on the $n_f=2+1+1$ MILC ensembles and using the Highly Improved Staggered Quark action for all valence quarks. We perform the calculation…
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…
Semileptonic B decays are studied on quenched anisotropic lattices using Symanzik improved glue, NRQCD heavy quark and D234 light quark actions. We employ constrained fits to extract ground state contributions to two- and three-point…
We present results for different observables in weak decays of pseudoscalar and vector mesons with a heavy $c$ or $b$ quark. The calculations are done in a nonrelativistic constituent quark model improved at some instances by heavy quark…
The decays governed by the flavor-changing-neutral-current transitions (FCNC), such as $b\to s\ell^{+}\ell^{-}$, provide an important tool to test the physics in and beyond the Standard Model (SM). This work focuses on investigating the…
Decays $B\to DP\ell^+\nu_\ell~(\ell=e,\mu,\tau)$ with the non-resonance, the charmed vector resonances, the charmed scalar resonances and the charmed tensor resonances are calculated by using the SU(3) flavor symmetry. Firstly, the decay…
Lattice Monte Carlo simulations now include the effects of 2 light sea quarks and 1 strange sea quark through the use of an improved staggered fermion action. Consequently, results important to phenomenology are free of the approximate 10%…
We present the new analysis of the semileptonic B decays in the framework of the relativistic quark model based on the quasipotential approach. Decays both to heavy D^{(*)} and light \pi(\rho) mesons are considered. All relativistic effects…
We investigate the exclusive semilpetonic decays of $\Lambda^{+}_{c}\to (\Lambda/n) \ell^{+} \nu_{\ell}~(\ell=e,\mu)$ within the standard model by using the light-front quark model (LFQM). The form factor behaviors are obtained from the…
We discuss how LHC di-muon data collected to study $B_q \to \mu\mu$ can be used to constrain light particles with flavour-violating couplings to $b$-quarks. Focussing on the case of a flavoured QCD axion, $a$, we compute the decay rates for…