Related papers: Extraction of |Vub| with Reduced Dependence on Sha…
We compute O(alpha_s^2) QCD corrections to the lepton invariant mass spectrum in the decay b --> u l nu_l, relevant for the determination of the CKM matrix element |V_{ub}|. Our method can also be used to evaluate moments of the lepton…
We calculate the form factor f_+(q^2) for B-meson semileptonic decay in unquenched lattice QCD with 2+1 flavors of light sea quarks. We use Asqtad-improved staggered light quarks and a Fermilab bottom quark on gauge configurations generated…
The following is an overview of the current status of charmless semileptonic B decays and the extraction of the CKM matrix element $|V_{ub}|$ by the Belle and BaBaR collaborations.
We review the status and future prospects of the determination of the CKM matrix element |V_us| using inclusive strange hadronic \tau{} decay data. We also review the results for |V_us| extracted from experimental measurements of some…
The differential branching fraction with respect to the dimuon invariant mass squared, and the $C\!P$ asymmetry of the $B^\pm\to\pi^\pm\mu^+\mu^-$ decay are measured for the first time. The CKM matrix elements $|V_{td}|$ and $|V_{ts}|$, and…
Experimental studies of charmless semileptonic B decays can be broadly categorized into inclusive and exclusive measurements depending on how the final states are treated. The inclusive method measures the decay rate $\Gamma(B \to X_u \ell…
We address the non-perturbative calculation of the decay rate of inclusive semi-leptonic $B_{(s)}$ mesons decays from lattice QCD. Precise theoretical Standard Model predictions are key ingredients in searches for new physics. This type of…
We use 429 fb$^{-1}$ of $e^+e^-$ collision data collected at the $\Upsilon(4S)$ resonance with the BABAR detector to measure the radiative transition rate of $b\rightarrow s\gamma$ with a sum of 38 exclusive final states. The inclusive…
The Cabibbo-Kobayashi-Maskawa (CKM) matrix element $\vert V_{ub}\vert$ is obtained from exclusive semileptonic $B \to \pi \ell \nu_\ell$ and $B_s \to K \ell \nu_\ell$ decays adopting the unitarity-based dispersion matrix approach for the…
We use recent Belle results on $\bar{B}^0\rightarrow D^{*+}l^-\bar{\nu}_l$ decays to extract the CKM element $|V_{cb}|$ with two different but well-founded parameterizations of the form factors. We show that the CLN and BGL…
We evaluate the most important tree-level contributions connected with the b-> u \bar{u} d gamma transition to the inclusive radiative decay \bar{B}-> X_d gamma using fragmentation functions. In this framework the singularities arising from…
We present an analysis of exclusive charmless semileptonic B-meson decays based on 377 million BBbar pairs recorded with the BABAR detector at the Upsilon(4S) resonance. We select four event samples corresponding to the decay modes B0 -->…
We propose a model-independent method to determine the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{ub}|$ from exclusive $B$ and $D$ decays. Combining information obtainable from $B\to \rho\ell\bar\nu_\ell$, $B\to…
Since the degree of polarization of the vector particle in semileptonic decay strongly influences the decay width of the particles, it can be used as a measure of CKM matrix elements. We show that |V_{cb}| can be determined from the…
We reduce the perturbative uncertainty in the determination of |V_{ub}| from inclusive semileptonic B decays by calculating the rate of B -> X_u l nu events with dilepton invariant mass q^2>(M_B-M_D)^2 at subleading order in the hybrid…
We measured two moments of the lepton momentum spectrum in B -> X l nu, where l= e or mu, for p_l > 1.5 GeV/c. From these we derive the Heavy Quark Expansion (HQE) parameters Lambda-bar(MS-bar) = 0.39 +- 0.03(stat) +- 0.06(sys) +- 0.12(th)…
We present the measurement of the first to fourth order moments of the four-momentum transfer squared, $q^2$, of inclusive $B \rightarrow X_c \ell^+ \nu_{\ell}$ decays using the full Belle data set of 711 $\mathrm{fb}^{-1}$ of integrated…
We compute the form factors parametrizing radiative leptonic decays of heavy mesons B^+\to\gamma e^+\nu for photon energies much larger than \Lambda_{QCD}, where perturbative QCD methods for exclusive processes can be combined with the…
We report the measurement of an inclusive partial branching fraction for charmless semileptonic B decay and the extraction of |V_ub|. Candidates for B -> X_u l nu are identified with a novel X_u-reconstruction method based on neutrino…
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…