相关论文: Status of the Hadronic Tau Determination of V_us
Selected results from tau analyses performed using the BaBar detector at the SLAC National Accelerator Laboratory are presented. A precise measurement of the tau mass and the tau{+} tau{-} mass difference is undertaken using the hadronic…
We show how sum rules for the weak decays of heavy flavor hadrons can be derived as the moments of spectral distributions in the small velocity (SV) limit. This systematic approach allows us to determine corrections to these sum rules, to…
In this note, recent results of studies of semileptonic B meson decays from \babar are discussed and preliminary results given. In particular, a recent measurement of $\mathcal{B}(B \to D^{(*)}\tau \nu)$ and the ratio $\mathcal{B}(B \to…
Various strategies for extracting or constraining the weak phase gamma with controlled theoretical uncertainties are reviewed. Measurements of the rates for the hadronic decays B^+- -> pi K provide largely model-independent information on…
Recent BABAR and Belle results on rare B decays involving photons or lepton pairs are reviewed. New preliminary limits from both experiments for B-->rho gamma and B-->omega gamma, and from BABAR for B --> K nu nu and B --> tau nu are…
Experimental studies of B -> D^(*) tau nu decays, are reported. The results are based on large data samples collected at the Upsilon(4S) resonance with the Belle detector at KEKB and the BABAR detector at the SLAC PEP-II asymmetric energy…
Recent measurements of branching fractions and CP-violating partial-rate asymmetries for rare hadronic B-meson decays by the asymmetric-energy B-factory experiments, Belle and BaBar, are reviewed.
This is a review of new results on the Tau lepton. The lifetime has been measured with improved precision, allowing the test of lepton universality to 0.2% level. There are several new measurements of the branching ratios for the hadronic…
We report on determinations of |Vub| resulting from studies of the branching fraction and q^2 distributions in exclusive semileptonic B decays that proceed via the b->u transition. Our data set consists of the 9.7x10^6 BBbar meson pairs…
Three important QCD-related aspects of the $\tau$ and $\mu$ dynamics are reviewed: the determination of the strong coupling from the hadronic tau decay width, leading to the updated value $\alpha_s(m_\tau^2) = 0.331 \pm 0.013$; the…
We present a general analysis of SU(3) breaking effects in the semi-inclusive tau hadronic width. The recent ALEPH measurements of the inclusive Cabibbo--suppressed decay width of the tau and several moments of its invariant mass…
Using about 23M $B \bar B$ events collected in 1999-2000 with the BABAR detector, we report on the decays $B \to D^{(*)}\bar D^{(*)}K$ and $B^0 \to D^{*+}D^{*-}$. The branching fractions of the low background decay modes $B \to D^{(*)}\bar…
We present a measurement of the branching fraction of $B^+\to\tau^+\nu_\tau$ decays using $(387\pm6)\times 10^6$ $\Upsilon(4S)$ collected between 2019 and 2022 with the Belle II detector at the SuperKEKB $e^+e^-$ collider. We reconstruct…
The branching fraction of the tau- --> 3h- 2h+ nu decay (h= pi, kaon) is measured with the BaBar detector to be (8.56 +/- 0.05 +/- 0.42)E-04 where the first error is statistical and the second systematic. The observed structure of this…
New preliminary BaBar results for rare leptonic decays $B^- \to K^-\nu \bar{\nu}$ and $B^0\to \ell^+\ell^-$ are reported. Using data collected at the $\FourS$ with the BaBar detector, no evidence for a signal was found yielding the…
By considering that the weak currents and the electromagnetic current are members of the same SU(3) octet, two sum rules involving leading vector form factors in hyperon semileptonic decays are derived in the limit of exact flavor SU(3)…
Semileptonic and leptonic B decays are analyzed in the framework of the relativistic quark model. Special attention is payed to the decays involving $\tau$ lepton. It is found that the calculated particular decay branching fractions are…
With the full data sample of $772 \times 10^6$ $B{\bar B}$ pairs recorded by the Belle detector at the KEKB electron-positron collider, the decay $\bar{B} \rightarrow D^* \tau^- \bar{\nu}_\tau$ is studied with the hadronic $\tau$ decays…
Hadronization in tau -> K K pi nu_tau decays is driven by both vector and axial-vector currents that we study, guided by the following principles: The 1/N_C expansion -worked out at leading order, considering only the contribution of the…
The QCD corrections to the R_{\tau}^{12} moment of the invariant mass distribution in hadronic decays of the tau lepton are discussed. The next-to-next-to-leading order prediction is shown to be stable with respect to change of the…