相关论文: $B$-flavor tagging at Belle II
We report on first measurements of branching fractions~($\mathcal{B}$) and CP-violating charge asymmetries~($\mathcal{A}$) in charmless $B$ decays at Belle~II. We use a sample of electron-positron collisions collected in 2019 and 2020 at…
The Belle II experiment at the SuperKEKB energy-asymmetric electron-positron collider is a substantial upgrade of the B factory facility at the Japanese KEK laboratory. Belle II collected a sample of $362~\mathrm{fb}^{-1}$ at the…
In CP violation measurements in asymmetric B-factory experiments, a determination of the B flavor of the neutral B mesons is necessary. A new method to this purpose using only three vectors of charged particles has been developed. This…
We present an improved comparison of the strong coupling of the gluon to light (q_l=u+d+s), c, and b quarks, determined from multijet rates in flavor-tagged samples of hadronic Z0 decays recorded with the SLC Large Detector at the SLAC…
High precision flavor physics measurements are an essential complement to the direct searches for new physics at the LHC. Such measurements will be performed using the upgraded Belle II detector and upgraded KEKB accelerator. The status of…
We present the result of the search for the rare $B$ meson decay of $B^+ \to \ell^{\,+} \nu_{\ell} \gamma$ with $\ell =e,\mu$. For the search the full data set recorded by the Belle experiment of $711 \, \mathrm{fb}^{-1}$ integrated…
We present a measurement of the B0 B0-bar oscillation frequency using a flavor tagging method based on correlations of B meson flavor with the charge of other particles produced in p p-bar collisions at sqrt{s} = 1.8 TeV. Such correlations…
After an introduction on the peculiarities of flavor-physics measurements at a hadron collider, and on the upgraded Collider Detector at Fermilab (CDF II), I show recent results on two-body B0 and B0s decays into charged, pseudo-scalar,…
The Belle II experiment aims to record 50 ab$^{-1}$ data with the high luminosity to be provided by the SuperKEKB asymmetric-energy electron-positron collider. The anticipated high statistics data enables us to perform studies of $B$ decays…
Many physics signals presently studied at the high energy collision experiments lead to final states with jets originating from heavy flavor quarks. This report reviews the algorithms for heavy flavor jets identification developed by the…
The Belle II experiment at the SuperKEKB energy-asymmetric $e^+ e^-$ collider is a substantial upgrade of the B factory facility at the Japanese KEK laboratory. The design luminosity of the machine is $8\times 10^{35}$ cm$^{-2}$s$^{-1}$ and…
We presented at Moriond EW 2025 a measurement of the branching fraction of $B\to\tau\nu$ decays using $(387\pm 6) \times 10^6$ $\Upsilon (4S)$ collected between 2019 and 2022 with the Belle~II detector at the SuperKEKB $e^+e^-$ collider. We…
The top quark sector is almost decoupled from lighter quark generations due to the fact that $V_{tb}\approx$~1. The current experimental measurements of $V_{tb}$ are compatible with the Standard Model expectations but are still dominated by…
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 $|V_{ub}|$…
This paper presents a novel tagging technique to measure the beauty-quark partial decay-width ratio $R_b$ and its forward-backward asymmetry $A_\text{FB}^b$ at the FCC-ee, using $\mathcal{O}(10^{12})$ $Z$-boson decays. The method is based…
Based on a sample of four million events collected by ALEPH from 1991 to 1995, a measurement of the forward-backward asymmetry in Z -> b-barb decays using inclusive final states is presented. High-performance tagging of b-barb events in a…
A method is proposed for tagging the flavor of neutral $B$ mesons in the study of CP-violating decay asymmetries. The method makes use of a possible difference in interactions in $B \pi$ or $B^* \pi$ systems with isospins 1/2 and 3/2, and…
We report a preliminary study of the branching fractions and $q^2$ distributions of exclusive charmless semileptonic B decays, using events tagged by fully reconstructing one of the $B$ mesons in a hadronic decay mode. These results are…
Precision studies of flavour-changing processes involving quarks and leptons provide a number of ways to improve knowledge of the Standard Model and search for physics beyond it. There are excellent short- and mid-term prospects for…
We present a comparison of the strong couplings of light ($u$,~$d$,~and~$s$), $c$, and $b$ quarks determined from multijet rates in flavor-tagged samples of hadronic $Z^0$ decays recorded with the SLC Large Detector at the SLAC Linear…