相关论文: |Vcb|, |Vub|, and Hqet at Cleo
We present a measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic limit for B->X_c e\nu transitions, using a sample of 88 million Upsilon(4S) decays recorded by the BABAR detector. Partial…
We study the success to describe hyperon semileptonic decays of four models that incorporate second-order SU(3) symmetry breaking corrections. The criteria to assess their success is by determining V_{us} in each of the three relevant…
We address the nonperturbative calculation of the inclusive decay rate of semileptonic $B_{(s)}$-meson decays from lattice QCD. Precise Standard-Model predictions are key ingredients in searches for new physics, and this type of computation…
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 report the results of a study of the exclusive semileptonic decays B->pi0lnu, B->pi+lnu, B->rho0lnu, B->rho+lnu and B->omegalnu, where l represents an electron or a muon. The events are tagged by fully reconstructing a second B meson in…
The status of heavy-quark decays as of summer 1999 is reviewed. New measurements of semileptonic B decays from LEP and from CLEO are reported and the status of determining the CKM parameters |Vcb| and |Vub| is assessed. Rare charmless…
This article describes a determination of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ from the decay $B^0\to D^{*-}\ell^+\nu_\ell$ using 711 fb$^{-1}$ of Belle data collected near the $\Upsilon(4S)$ resonance. We simultaneously…
With ~10fb$^{-1}$ data from Belle, the results of b to c and u decays have been represented here. Several decay modes have been studied, which include charmonium, semileptonic decay and Cabibbo-suppressed decays mode. The preliminary…
The current status of the determinations of CKM matrix element |Vub| via exclusive and inclusive charmless semileptonic B decays is reviewed.
We report on the measurement of inclusive charmless semileptonic B decays $B \to X_{u} \ell \nu$. The analysis makes use of hadronic tagging and is performed on the full data set of the Belle experiment comprising 772 million $B\bar{B}$…
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…
We present a measurement of $|V_{ub}|$ from a simultaneous study of the charmless semileptonic decays $B^0\to\pi^- \ell^+ \nu_{\ell}$ and $B^+\to\rho^0 \ell^+\nu_{\ell}$, where $\ell = e, \mu$. This measurement uses a data sample of 387…
We report on the current status of semi-leptonic $B_{(s)}$ decays, including rare decays, and the extraction of the absolute values of the CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$.
The Cabibbo-suppressed semileptonic decay $B^{+}\to p\overline{p}\mu^{+}\nu_{\mu}$ is observed for the first time using a sample of $pp$ collisions corresponding to an integrated luminosity of 1.0, 2.0 and 1.7fb$^{-1}$ at centre-of-mass…
The measured $\bar{B}\to D^{(*)} l \bar\nu$ decay rates for light leptons ($l=e,\mu$) constrain all $\bar{B}\to D^{(*)}$ semileptonic form factors, by including both the leading and ${\cal O}(\Lambda_{\text{QCD}}/m_{c,b})$ subleading…
We determine the CKM matrix-element magnitude $|V_{cb}|$ using $\overline{B}^0\to D^{*+}\ell^-\bar\nu_\ell$ decays reconstructed in $189 \, \mathrm{fb}^{-1}$ of collision data collected by the Belle II experiment, located at the SuperKEKB…
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 measurement of the first four moments of the hadronic mass distribution in B->Xc lv decays is presented for minimum lepton momenta varying between 0.9 and 1.6 GeV, using data recorded with the BaBar detector. Furthermore, a measurement of…
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…
Recent progress in calculating O(alpha_s^2) corrections to inclusive and exclusive semileptonic b-->c transitions is reviewed. The impact of these corrections on the |V_cb| determination from both inclusive and exclusive B decays is…