Related papers: CKM Sides: Theory
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…
Determinations of CKM matrix elements are clouded by uncertainties in nonperturbative QCD parameters that relate measurable quantities to the underlying parton-level processes. A principal goal of the CLEO-c program is to provide precision…
The CKM matrix elements $V_{td}$, $V_{ts}$ and $V_{tb}$, while notoriously hard to measure directly in experiment, can be determined to great precision within the Standard Model (SM) with a minimal set of observables due to unitarity of…
We present recent BESIII results about the study of mesons which contain at least one charm quark. We determined the D(s)+ decay constants, the form factors of D semi-leptonic decays, the CKM matrix elements |Vcs(d)|.
Some emerging difficulties in the theoretical description of exclusive semileptonic $\bar B$ decays are discussed in the context of the quark model. While there are no unambiguous problems at this time, I discuss physics beyond the valence…
We report on studies of three types of B-meson decay that can contribute to an understanding of fundamental intergenerational quark mixing, charge-conjugation--parity violation, and long-distance quantum chromodynamics. Specifically, we…
We discuss the calculation of the inclusive semileptonic decay for the process $B_s \to X_c \, l \nu_l$ using lattice QCD. This calculation could be decisive in understanding the long-standing tension between inclusive and exclusive…
The principal difficulty in deducing weak interaction properties from experimental measurements of $B$-decays lies in controlling the strong interaction effects. In this talk I review the status of theoretical calculations of the amplitudes…
The determination of $|V_{cb}|$ using inclusive and exclusive (semi-)leptonic decays exhibits a long-standing tension of varying ${\cal O}(3 \sigma)$ significance. For the inclusive determination the decay rate is expanded in $1/m_b$ using…
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…
In this paper, we report on the results of the |Vcb| and |Vub| measurements obtained from studies of inclusive and exclusive semileptonic decays using 30fb^-1 of e^+e^- collision data collected by the Belle detector at KEKB.
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 $R(D^{*})$…
We review the progress on the determination of the CKM matrix elements |V_cs|, |V_cd|, |V_cb|, |V_ub| and heavy quark masses presented at the 6th International Workshop on the CKM Unitarity Triangle.
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…
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…
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…
Heavy Quark Expansions for semileptonic decays of beauty hadrons are briefly reviewed. I analyze how $|V(cb)|$ can be extracted from the semileptonic width of $B$ mesons, the average semileptonic width of all weakly decaying beauty hadrons…
We study semi-inclusive charmless decays $B \to \pi X$ in detail, such as $\bar B^0 \to \pi^{\pm (0)} X$, $B^0 \to \pi^{\pm (0)} X$, $B^{\pm} \to \pi^{\pm (0)} X$, where $X$ does not contain a charm (anti)quark. We find that the process…
It was recently pointed out that the decays B^+ --> D^{*+}_s gamma and B^+ --> D^{*+} gamma can be used for an extraction of |V_{ub}|. The theory of these decays is poorly understood. It was shown that in a world of almost degenerate b and…
In these proceedings, we explore the possible reach of the LHCb dataset in the area of charm semileptonic decays. Specifically, we give prospects for the measurement of $|V_{cs}|/|V_{cd}|$ using $\mathcal{B}(D^0\to…