Related papers: Long-Distance Contributions to the $\Lambda_b\righ…
We present a lattice QCD calculation of $B\to \pi l \nu$ semileptonic decay form factors in the small pion recoil momentum region. The calculation is performed on a quenched $16^3 \times 48$ lattice at $\beta=5.9$ with the NRQCD action…
The exclusive semileptonic decay form factors and widths of $B_c$ meson in the $c\bar c\ (\eta_c,J/\psi)$ states based on heavy quark effective theory are computed. The spectroscopic parameters of $B_c$ and the $c\bar c$ states deduced…
This paper describes the calculation of the semileptonic K_l3 decay form factor at order p^6 of chiral perturbation theory which is the next-to-leading order correction to the well-known p^4 result achieved by Gasser and Leutwyler. At order…
We present a QCD sum rule calculation of the Isgur-Wise form-factor tau_1(v.v') and tau_2(v.v') for the semileptonic decays B->D_1(2420)l\bar\nu and B->D_2^*(2460)l\bar\nu in the framework of heavy quark effective theory. These two…
Heavy quark symmetry predicts the value of $B \rightarrow D$ and $B \rightarrow D^*$ transition matrix elements of the current $\bar c \gamma_\mu (1 - \gamma_5)b$, at zero recoil (where in the rest frame of the $B$ the $D$ or $D^*$ is also…
The formalism and applications of chiral perturbation theory for hadrons containing a single heavy quark are discussed. We emphasize the utility of working directly with the velocity dependent ``super'' fields which appear in the chiral…
We update QCD calculations of $B \to \pi, K$ form factors at large hadronic recoil by including the subleading-power corrections from the higher-twist $B$-meson light-cone distribution amplitudes (LCDAs) up to the twist-six accuracy and the…
In view of new precise measurements of the $\bar B\to D^*\ell \bar\nu$ decay rate near zero recoil, we reconsider the theoretical uncertainties in the extraction of $| V_{cb}|$ using heavy quark symmetry. In particular, we combine our…
Under a rescaling of longitudinal coordinates $x^{0,3}$ by a factor $\lambda$ which is taken to zero, the classical QCD action simplifies dramatically. This is the high-energy limit, as $\lambda$ is of order $s^{-1/2}$, where $s$ is the…
In earlier publications we have analyzed the strong and radiative decays of heavy hadrons in a formalism which incorporates both heavy-quark and chiral symmetries. In particular, we have derived a heavy-hadron chiral Lagrangian whose…
We investigate the form factors for exclusive semileptonic decays of $B$-meson to $D,~D^*$, based on the parton picture and helped by the results of the HQET. We obtain the numerical results for the slope of the Isgur-Wise function, which…
We present preliminary results for various electroweak form factors of pseudo-scalar mesons using the tree-level improved Symanzik gauge action and the maximally twisted mass fermionic action with Nf = 2 dynamical flavors. Our results,…
We describe two recent theoretical calculations of the $B \to K^* \gamma$ decay. The first method is based on an effective lagrangian incorporating chiral symmetry for the light degrees of freedom and the heavy quark spin-flavor symmetries…
We calculate the two form-factors for the four Kaon to pion transitions via a vector current to order $p^6$ in Chiral Perturbation Theory to first order in isospin breaking via the quark masses. In addition we derive relations between these…
Heavy quark effective theory can be used to calculate the values of the semileptonic B^(*) -> D^(*) decays in the limit that the heavy quark masses are infinite. We calculate the lowest order chiral corrections, which are of O(1/M^2), from…
Using dispersion theory, the electromagnetic Sigma-to-Lambda transition form factors are expressed as the product of the pion electromagnetic form factor and the $\Sigma\bar{\Lambda}\to\pi\pi$ scattering amplitudes with the latter estimated…
We introduce an effective lagrangian including negative and positive parity heavy mesons containing a heavy quark, light pseudoscalars, and light vector resonances, with their allowed interactions, using heavy quark spin-flavour symmetry,…
We use the chiral quark model to estimate the coefficients of the weak chiral lagrangian as obtained from the bosonization of the ten relevant operators of the $\Delta S = 1$ effective quark lagrangian. All contributions of order $N_c^2$ as…
Using the heavy quark effective theory, chiral structure of the $b\rightarrow c$ charged current can be determined by the semileptonic $\Lambda_b$ decay with satisfactory theoretical accuracy. We define an asymmetry which is sensitive to…
In order to extract some information on the CKM matrix element |Vcb|, we have to determine form factors in B decays. For this, we show that it is relevant to consider the non-forward amplitude between the heavy-light B and D mesons within…