相关论文: A novel method of reconstructing semileptonic $B$ …
We study the exclusive semileptonic $B$-meson decays $B\to K(\pi)\ell^+\ell^-$, $B\to K(\pi)\nu\bar\nu$, and $B\to\pi\tau\nu$, computing observables in the Standard model using the recent lattice-QCD results for the underlying form factors…
Presented are selected results of semileptonic B decays at BaBar. Two measurements of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ are reported. One using moments of the hadronic-mass spectrum in inclusive $\bar{B} \to X_{c}…
We present an application of the unitarity-based dispersion matrix (DM) approach to the extraction of the CKM matrix element $|V_{cb}|$ from the experimental data on the exclusive semileptonic $B_{(s)} \to D_{(s)}^{(*)} \ell \nu_\ell$…
The study of the purely leptonic decays of the ground charged vector mesons is very interesting and significant in determining the CKM matrix elements, obtaining the decay constant of vector mesons, examining the lepton flavor universality,…
We introduce a new method for selecting exclusive semileptonic charmless B-decays in the presence of a large background. The method can be applied to charged and neutral B-mesons decaying into any exclusive neutral or charged hadronic final…
We present a preliminary determination of the CKM matrix element |Vub| based on the analysis of semileptonic B decays from a sample of 88 million Upsilon(4S) decays collected with the BaBar detector at the e+e- storage ring. Charmless…
Data in $B$-meson decays indicate violations of lepton flavour universality, thereby raising the question about such phenomena in the charm sector. We perform a model-independent analysis of NP contributions in (semi)-leptonic decays of…
We report new measurements, based on the Run I dataset collected by the LHCb experiment, of the B0 mixing frequency Dm_d and the CKM matrix element |V_ub| using semileptonic b decays. The former is the most precise measurement ever…
We perform a study of the $B^{(*)}$, $D^{(*)}$ semileptonic decays, using a different method than in conventional approaches, where the matrix elements of the weak operators are evaluated and a detailed spin-angular momentum algebra is…
We present a preliminary measurement of the composition of inclusive semileptonic B meson decays using 9.4 fb^{-1} of e^+e^- data taken with the CLEO detector at the Upsilon(4S) resonance. In addition to measuring the charged lepton…
We review the current status of experimental measurements of the branching fractions for exclusive semileptonic decays of B mesons to charmless hadrons and the determination of the Standard Model CKM parameter |Vub| from these measurements.
It has been proposed to determine the CKM matrix element |V_ub| in a model-independent way from a combination of rare and semileptonic B and D decays near the zero recoil point. An essential ingredient in such a determination is a heavy…
We present measurements of the first six hadronic mass moments in semileptonic $B \rightarrow X_c \ell \nu $ decays. The hadronic mass moments, together with other observables of inclusive $B$ decays, can be used to determine the CKM matrix…
Charmless semileptonic decays, ${\bar{B}} \to X_u \ell \bar{\nu}$, are studied in a sample of 232 million $B\bar{B}$ decays recorded with the BaBar detector, in events where the decay of the second $B$ meson is fully reconstructed.…
Two of the elements of the Cabibbo-Kobayashi-Maskawa quark mixing matrix, $|V_{ub}|$ and $|V_{cb}|$, are extracted from semileptonic B decays. The results of the B factories, analysed in the light of the most recent theoretical…
A summary of WG II of the CKM 2018 conference on semileptonic and leptonic $b$-hadron decays is presented. This includes discussions on the CKM matrix element magitudes $|V_{ub}|$ and $|V_{cb}|$, lepton universality tests such as $R(D^{*})$…
The leptonic and semileptonic decay propertis of Bc mesons are studied in a QCD potential model. The CKM element for the leptonic decay is calculated by evaluating its decay constant. With the help of the Isgur-Wise function, the form…
We demonstrate the feasibility of determining the strong coupling constant, $\alpha_s$, from the inclusive semileptonic decay width of $B$ mesons. We express the semileptonic $B$ decay width as a function of $\alpha_s(5\mathrm{\,GeV})$, the…
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…
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…