Related papers: CKM matrix element Vcb in a QCD Potential model
We present a measurement of the branching fraction for the rare decays B->rho e nu and extract a value for the magnitude of Vub, one of the smallest elements of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix. The results are given for…
In the framework of heavy quark effective theory, the leading order Isgur-Wise form factors relevant to semileptonic decays of the ground state $\bar{b}s$ meson $B_{s}$ into orbitally excited $D$-wave $\bar{c}s$ mesons, including the newly…
The slope of the Isgur-Wise function for ground state mesons is evaluated for the heavy mass limit of quark models \`a la Bakamjian-Thomas, which has been previously discussed by us in general terms. A full calculation in various…
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…
The quark flavor sector of the Standard Model is a fertile ground to look for new physics effects through a unitarity test of the Cabbibo-Kobayashi-Maskawa (CKM) matrix. We present a lattice QCD calculation of the scalar and the vector form…
I report on recent developments in the heavy-quark effective theory and its application to $B$ meson decays. The parameters of the effective theory, the spin-flavor symmetry limit, and the leading symmetry-breaking corrections to it are…
In this talk I review the status of our ability to extract the CKM matrix elements Vub and Vcb from inclusive semileptonic decays. I focus on model independent determinations of these parameters and discuss the expected theoretical…
Semileptonic, B --> pi l,nu, decays are studied on the MILC dynamical configurations using NRQCD heavy and Asqtad light quarks. We work with light valence quark masses ranging between m_s and m_s/8. Preliminary simple linear chiral…
The 1/m_c and 1/m_b corrections to the \Lambda_b to \Lambda_c semi- leptonic decay are analyzed by QCD sum rules. Within the framework of heavy quark effective theory,the subleading baryonic Isgur-Wise func- tion of \Lambda_b to \Lambda_c…
The following is an overview of the measurements of the CKM matrix elements V_cb and V_ub that are based on detailed studies of semileptonic B decays by the BABAR and Belle Collaborations and recent advances in QCD calculations. In…
In connection with planned experiments devoted to investigation of semileptonic decays of beauty baryons Isgur-Wise function and observables of $\Lambda_b$ baryon (decay rates and distributions, leptonic spectra and asymmetry parameters)…
Using BaBar measurements of the inclusive electron spectrum in B->X_u e nu decays and the inclusive photon spectrum in B->X_s gamma decays, we extract the magnitude of the CKM matrix element Vub. The extraction is based on theoretical…
We report measurements of partial branching fractions for inclusive charmless semileptonic B decays Bbar --> Xu l nubar, and the determination of the CKM matrix element |V_{ub}|. The analysis is based on a sample of 467 million Upsilon(4S)…
A reliable determination of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ is mandatory for precision flavor physics and for the search for CP violating phases from new, heavy particles. In this article, we review the theory of the…
We investigate the quark structure of D and B mesons in the framework of a constituent quark model. To this end, we assume a scalar confining and a one gluon exchange (OGE) potential. The parameters of the model are adopted to reproduce the…
An explicit relativistic light-front quark model is presented which gives the momentum transfer dependent form factors of weak hadronic currents among heavy pseudoscalar and vector mesons in the whole accessible kinematic region $ 0\leq q^2…
In this work we investigate the weak $\Lambda_{b}\to\Lambda_c$ semi-leptonic and non-leptonic decays. The light-front quark model and diquark picture for heavy baryons are adopted to evaluate the $\Lambda_{b}\to\Lambda_c$ transition form…
Semileptonic ${B}$ meson decays involving low-mass charged leptons ${e}$ or ${\mu}$ are expected to be free of non-Standard Model contributions and therefore play a critical role in determinations of ${\vert V_{ub} \vert}$ and ${\vert…
Nonperturbative QCD contributions to the inclusive semileptonic decay of the B meson consist of the dynamic and kinematic components. We calculate the decay width in an approach based on the light-cone expansion and the heavy quark…
Considering the Cornell potential $V(r)=-\frac{4\alpha_s}{3r}+br+c$, we have revisited the Dalgarno's method of perturbation by incorporating two scales $r^{short}$ and $r^{long}$ as integration limit so that the perturbative procedure can…