Related papers: Extracting |V(ub)| from B->pi l nu Decays Using a …
We summarize selected up-to-date results related to semileptonic $B$ meson decays, namely results on the exclusive determination of the parameter $|V_{cb}|$ of the CKM matrix, on the inclusive determination of $|V_{ub}|$, and on…
I discuss the results for $|V_{ub}|$ obtained from $B\to\pi e \nu$ using the form factor $f_+(q^2)$ from QCD sum rules on the light-cone and unquenched lattice calculations; the shape of $f_+(q^2)$ is fixed from experimental data.
We perform the simultaneous $|V_{ub}|$ and $|V_{cb}|$ extractions with only the exclusive $\Lambda_b$ decays of $\Lambda_b\to (p,\Lambda_c^+)\mu\bar \nu_\mu$, $\Lambda_b\to p\pi^-$ and $\Lambda_b\to \Lambda_c^+ (\pi^-, D^-)$. We obtain that…
We study exclusive nonleptonic and semileptonic decays of the Bc-meson within a relativistic constituent quark model previously developed by us. For the nonleptonic decays we use the factorizing approximation. We update our model parameters…
The experimental prospects for precise measurements of the leptonic decays B_u -> tau nu / mu nu, B_s -> mu+ mu-, D -> mu nu and D_s -> mu nu / tau nu are very promising. Double ratios involving four of these decays can be defined in which…
We use rigorous QCD dispersion relations to derive model-independent bounds on the B -> pi l nu, D -> pi l nu and D -> K l nu form factors. These bounds are particularly restrictive when the value of the observable form factor at one or…
We report the results of a study of the exclusive charmless semileptonic B0->pilnu decay undertaken with approximately 227 million BBbar pairs collected at the Upsilon(4S) resonance with the BABAR detector. The analysis uses events in which…
Following a strategy introduced earlier by the authors, we show that it is possible to extract |V_{ub}| from the cut hadronic mass spectrum of B decays without large systematic errors which usually arise from having to model the Fermi…
We present the results of a lattice computation of the form factors for B^0 ->pi^- l^+nu_l decays near zero-recoil. These results will allow a determination of the CKM matrix element |Vub| when measurements of the differential decay rate…
The form factors of semileptonic $B_{(s)}\to a_{1}(K_1)\, \ell^{+}\ell^{-}$, $ \ell=\tau,\mu,e$ transitions are investigated in the framework of the light-cone sum rules with $B$-meson distribution amplitudes, which play an important role…
The method of calculating electroweak decay matrix elements between heavy-heavy and heavy-light meson states is developed in the framework of relativistic quark model based on the quasipotential approach in quantum field theory. This method…
In light of the first observation of the semileptonic decay $B^{0}_{s}\to K^{-}\mu^{+}\nu_{\mu}$ by the LHCb collaboration, we revisit the determination of the CKM parameter $|V_{ub}|$ from exclusive semileptonic $B$-meson decays. A…
Strong interaction effects are addressed in connection to extracting |V_{cb}|. A comprehensive approach is described not relying on a 1/m_c expansion; it allows a percent accuracy without ad hoc assumptions about higher-order effects. An…
We report measurements of branching fractions for the decays B --> P l nu, where P are the pseudoscalar charmless mesons pi-, pi0, eta and eta', based on 348 fb-1 of data collected with the BABAR detector, using B0 and B+ mesons found in…
The form factors for the $B-->\pi$ transition are evaluated in the entire momentum transfer range by using the constraints obtained in the framework combining the heavy quark expansion and chiral symmetry for light quarks and the quark…
The inclusive direct and cascade semileptonic branching ratios of the b quark were measured from a fit to the lepton momentum spectrum in the B-hadron rest frame, exploiting the charge correlation between the lepton and the heavy meson. The…
We present a measurement of the electron spectrum from inclusive semileptonic {\it B} decay, using 5.1 fb$^{-1}$ of $\Upsilon(4S)$ data collected with the Belle detector. A high-momentum lepton tag was used to separate the semileptonic {\it…
A shape-function independent relation is derived between the partial B->X_u+l+nu decay rate with a cut on P_+=E_X-P_X<Delta and a weighted integral over the normalized B->X_s+gamma photon-energy spectrum. The leading-power contribution to…
Physics beyond the Standard Model could be measured indirectly, through its effects on Standard Model observables. One place to look for such effects is in the semileptonic decays of B mesons. In order to constrain the possible role of new…
In this work we apply the Dispersive Matrix (DM) method of Refs. [1,2] to the lattice computations of the Form Factors (FFs) entering the semileptonic $B \to D^* \ell \nu_\ell$ decays, recently produced by the FNAL/MILC Collaborations [3]…