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Related papers: Loopy Determinations of $V_{ub}$ and $V_{cb}$

200 papers

For the determination of the Cabbibo-Kobayashi-Maskawa matrix element $|V_{cb}|$ from inclusive data a precise knowledge of the semileptonic $b \to c$ decay rate is necessary. Since this observable has a bad convergence behavior when the…

High Energy Physics - Phenomenology · Physics 2022-04-01 Kay Schönwald

The determination of the CKM element $V_{cb}$ from inclusive semileptonic $b\to c \ell \bar\nu$ decays has reached a high precision thanks to a combination of theoretical and experimental efforts. Aiming towards even higher precision, we…

High Energy Physics - Phenomenology · Physics 2021-09-29 Thomas Mannel , Muslem Rahimi , K. Keri Vos

I discuss the theoretical uncertainties in the extraction of $|\,V_{cb}|$ from semilep\-to\-nic decays of $B$ mesons, taking into account the most recent theoretical developments. The main sources of uncertainty are identified both for the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthias Neubert

We perform global fits to the moments of semileptonic B decay distributions and extract |V_cb|, the heavy quark masses, and the non-perturbative parameters of the heavy quark expansion. We include NNLO perturbative corrections and recent…

High Energy Physics - Phenomenology · Physics 2014-01-29 Paolo Gambino , Christoph Schwanda

We review many lattice QCD calculations that impact the precise determination of the CKM matrix. We focus on decay constants and semileptonic form factors of both light ($\pi$ and K) and heavy-light ($D_{(s)}$ and $B_{(s)}$) mesons.…

High Energy Physics - Lattice · Physics 2019-01-01 Steven Gottlieb

The persistent tensions between inclusive and exclusive determinations of $|V_{cb}|$ and $|V_{ub}|$ weaken the power of theoretically clean rare $K$ and $B$ decays in the search for new physics (NP). We demonstrate how this uncertainty can…

High Energy Physics - Phenomenology · Physics 2022-03-22 Andrzej J. Buras , Elena Venturini

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…

High Energy Physics - Experiment · Physics 2007-05-23 Martino Margoni

We propose a novel method of measuring the CKM matrix element V_ub, via inclusive B decays to "wrong sign" charm. This process is mediated by the quark level decay b -> u cbar s'. When normalized to the inclusive semileptonic decay rate,…

High Energy Physics - Phenomenology · Physics 2011-01-25 Adam F. Falk , Alexey A. Petrov

A largely model-independent measurement of the inclusive electron momentum spectrum and branching fraction for semileptonic decays of B mesons is presented based on data recorded at the Upsilon(4S) resonance with the BABAR detector.…

High Energy Physics - Experiment · Physics 2008-11-26 B. Aubert

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…

High Energy Physics - Phenomenology · Physics 2009-10-30 Andrzej Czarnecki , Kirill Melnikov

Semileptonic ${B}$ meson decays involving low-mass charged leptons ${e}$ or ${\mu}$ are expected to be free of non-Standard Model contributions and therefore play a critical role in determinations of ${\vert V_{ub} \vert}$ and ${\vert…

High Energy Physics - Experiment · Physics 2019-08-13 Matic Lubej

Exclusive semileptonic B decays are discussed. The emphasis is on using semileptonic decays to determine |V_{ub}| and |V_{cb}|. Recent progress in our understanding of B semileptonic decays to excited charmed mesons is also reviewed.

High Energy Physics - Phenomenology · Physics 2014-11-17 Mark B. Wise

Recent results on inclusive charmless semileptonic decays of B mesons are reviewed. Emphasis is given to measurements on the recoil of fully reconstructed B mesons, which allow to exploit several regions of phase space. Preliminary averages…

High Energy Physics - Experiment · Physics 2011-01-24 Concezio Bozzi

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 $|V_{ub}|$.

High Energy Physics - Phenomenology · Physics 2014-06-13 Giulia Ricciardi

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…

High Energy Physics - Lattice · Physics 2023-07-26 Alessandro Barone , Shoji Hashimoto , Andreas Jüttner , Takashi Kaneko , Ryan Kellermann

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…

High Energy Physics - Lattice · Physics 2026-04-30 Alessandro Barone , Ahmed Elgaziari , Shoji Hashimoto , Zhi Hu , Andreas Jüttner , Takashi Kaneko , Ryan Kellermann

I report results from the CLEO collaboration on semileptonic B decays, highlighting measurements of the Cabibbo-Kobayashi-Maskawa matrix elements Vcb and Vub. I describe the techniques used to obtain the recent improvements in precision for…

High Energy Physics - Experiment · Physics 2019-08-14 Karl M. Ecklund

The use of inclusive B decays to determine |V_{ub}|, |V_{cb}|, m_b and heavy quark matrix elements via spectral moments is discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 Michael Luke

For a long time there have been active discussions about the sizable differences between $|V_{ub}|_{\rm incl}$ \& $|V_{ub}|_{\rm excl}$. However, the real $|V_{ub}|_{\rm incl}$ might be smaller than usually stated. The connection of the…

High Energy Physics - Phenomenology · Physics 2015-09-23 Ikaros I. Bigi

We use recent Belle results on $\bar{B}^0\rightarrow D^{*+}l^-\bar{\nu}_l$ decays to extract the CKM element $|V_{cb}|$ with two different but well-founded parameterizations of the form factors. We show that the CLN and BGL…

High Energy Physics - Phenomenology · Physics 2017-04-27 Dante Bigi , Paolo Gambino , Stefan Schacht