相关论文: Recent CLEO CKM Results
We determine the inclusive B --> Xc l nu branching fraction, the CKM matrix element |Vcb|, and other heavy-quark parameters from a simultaneous fit to moments of the hadronic-mass and lepton-energy distributions in semileptonic B-meson…
A sample of 365 fb$^{-1}$ of $e^+e^- \to \Upsilon(4S) \to B\bar{B}$ data collected by the Belle II experiment is used to measure the partial branching fractions of charmless semileptonic $B$ meson decays and determine the magnitude of the…
We present the partial branching fraction for inclusive charmless semileptonic B decays and the corresponding value of the CKM matrix element |Vub|, using a multivariate analysis method to access ~90% of the B -> Xu l nu phase space. This…
The determination of the Vub element of the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix plays a central role in testing the Standard Model (SM) interpretation of CP violation. Measurements at B-Factories are contributing with…
Moments of B -> X l nu and B -> Xs gamma decays can determine nonperturbative QCD parameters that relate the semileptonic decay width to Vcb. CLEO pioneered measurement of these moments, determined the relevant QCD parameters from the…
We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element |V_ub|, based on 253 fb^-1 of data collected by the Belle detector at the KEKB e^+e^- asymmetric collider. Events are tagged by fully reconstructing one of the B…
Recent advances in improving extractions of |Vcb| and m_b from spectra of semileptonic inclusive B decay are reported. Results of a general moment analysis of the lepton energy spectrum and the hadronic invariant mass spectrum are…
We present two recent measurements of semileptonic B decays at Belle, offering valuable insights into the determination of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element $|V_{ub}|$. These analyses use the full Belle dataset, comprising…
BaBar measurements involving semileptonic decays of B mesons are reviewed. Attention is focused on the extraction of |Vub| and |Vcb| elements of the Cabibbo-Kobayashi-Maskawa quark mixing matrix. Recent results of inclusive and exclusive…
The Belle experiment at the KEKB asymmetric energy e+e- collider recorded large data sets of both, B and Bs decays. Semileptonic decays B(s) -> X l nu (l = electron or muon) constitute approximately one fifth of the total decay width of…
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 report on studies of exclusive and inclusive semileptonic b -> ul\nu and b -> cl\nu decays in 9.7 million B\barB events accumulated with the CLEO detector in symmetric e^+e^- collisions produced in the Cornell Electron Storage Ring…
Charged current semi-leptonic decays of $B$-meson are important for a precise determination of the CKM elements. The CKM elements $|V_{ub}|$ and $|V_{cb}|$ show a discrepancy between the exclusive and inclusive determinations. These…
The paper summarizes recent results from the Belle and Belle II collaborations on semileptonic $B$ decays measurements including inclusive and exclusive determination of Cabibbo-Kobayashi-Maskawa matrix elements $|V_{cb}|$ and $|V_{ub}|$…
In order to determine the ratio of CKM matrix elements |V_{ub}/V_{cb}| (and |V_{ub}|), we propose a new model-independent method based on the heavy quark effective theory, which is theoretically described by the phase space factor and the…
The ratio of the CKM quark-mixing matrix elements |Vub|/|Vcb| has been measured using B hadron semileptonic decays. The analysis uses the reconstructed mass M_X of the secondary hadronic system produced in association with an identified…
We present an analysis of the Belle measured moments of the lepton energy and hadronic mass spectra in B -> X_c l nu decays and the photon energy spectrum in B -> X_s gamma decays using theoretical expressions derived in the 1S and kinetic…
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 report studies of semileptonic decays, B --> X_c l nu, based on a sample of 88 million BB events recorded with the BABAR detector. We have measured four moments of the electron energy distribution and four moments of the hadronic mass…
The CKM matrix element amplitude |V_cb| was determined using the data collected by the BABAR detector. The partial branching fraction, lepton-energy moments, and hadron-mass moments were measured in inclusive semileptonic decays B -> X_c l…