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Related papers: Tensions and correlations in $|V_{cb}|$ determinat…

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We report a strong tension in $\varepsilon_K$ at the $4\sigma$ level between the experimental value and the theoretical value calculated directly from the standard model using lattice QCD inputs such as $\hat{B}_K$, $|V_{cb}|$, $|V_{us}|$,…

High Energy Physics - Lattice · Physics 2018-11-21 Jon A. Bailey , Sunkyu Lee , Weonjong Lee , Jaehoon Leem , Sungwoo Park

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…

High Energy Physics - Phenomenology · Physics 2016-05-25 Sascha Turczyk

The determination of $|V_{cb}|$ from exclusive semileptonic $B\to D^*\ell\nu$ decays is sensitive to the choice of form factor parametrization. Larger $|V_{cb}|$ values are obtained fitting the BGL versus the CLN parametrization to recent…

High Energy Physics - Phenomenology · Physics 2019-07-31 Florian U. Bernlochner , Zoltan Ligeti , Dean J. Robinson

The 2012 PDG reports a tension at the level of $3 \sigma$ between two exclusive determinations of $|V_{ub}|$. They are obtained by combining the experimental branching ratios of $B \to \tau \nu$ and $B \to \pi l \nu$ (respectively) with a…

High Energy Physics - Lattice · Physics 2012-11-28 F. Bahr , F. Bernardoni , B. Blossier , J. Bulava , M. Della Morte , P. Fritzsch , N. Garron , A. Gérardin , J. Heitger , G. von Hippel , A. Ramos , H. Simma , R. Sommer

Stringent relations between the $B^{(*)} \to D^{(*)} $ form factors exist in the heavy quark limit and the leading symmetry breaking corrections are known. We reconsider their uncertainty and role in the analysis of recent Belle data for…

High Energy Physics - Phenomenology · Physics 2017-12-06 Dante Bigi , Paolo Gambino , Stefan Schacht

We report on the determination of $|V_{cb}|$ from the comparison of the semileptonic inclusive decay rates of B-- and D--mesons using the heavy quark symmetry of QCD. While the renormalization scale ambiguity does not allow for a reliable…

High Energy Physics - Phenomenology · Physics 2010-11-01 U. Nierste

We reconsider the possibility that the tension in the $|V_{cb}|$ determinations from inclusive and exclusive $B$ decay modes is due to a new physics effect. We modify the Standard Model effective Hamiltonian for semileptonic $b \to c$…

High Energy Physics - Phenomenology · Physics 2017-02-01 Pietro Colangelo , Fulvia De Fazio

Our Vcb extraction is based on recent Belle results, with unfolded kinematical dependence. We use two different parameterizations of the form factors, the CLN and BGL parameterizations. We discuss how the known discrepancy between the…

High Energy Physics - Phenomenology · Physics 2018-08-27 Vincenzo Afferrante , Guido Martinelli

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 fit the unfolded data of $\bar{B}^0\rightarrow D^{*+} \ell \overline{\nu}$ from the Belle experiment, where $\ell \equiv e, \mu$, using a method independent of heavy quark symmetry to extrapolate to zero-recoil and extract the value of…

High Energy Physics - Phenomenology · Physics 2017-06-09 Benjamin Grinstein , Andrew Kobach

$B$ processes are a rich source of potential anomalies that could lead to the discovery of BSM physics. The long-standing tension between the inclusive and the exclusive determinations of the CKM matrix elements $|V_{xb}|$, or the current…

High Energy Physics - Phenomenology · Physics 2025-04-11 Alejandro Vaquero Aviles-Casco

In view of new precise measurements of the $\bar B\to D^*\ell \bar\nu$ decay rate near zero recoil, we reconsider the theoretical uncertainties in the extraction of $| V_{cb}|$ using heavy quark symmetry. In particular, we combine our…

High Energy Physics - Phenomenology · Physics 2010-11-01 M. Neubert

The most common predictions for rare $K$ and $B$ decay branching ratios in the Standard Model are based on the CKM elements $|V_{cb}|$ and $|V_{ub}|$ resulting from global fits, that are in the ballpark of their inclusive and exclusive…

High Energy Physics - Phenomenology · Physics 2022-08-10 Andrzej J. Buras , Elena Venturini

We compute the complete set of SM and tensor $B_{(s)}\to D_{(s)}^*\ell\bar{\nu}$ semileptonic form factors across the full kinematic range of the decay using second generation MILC $n_f=2+1+1$ HISQ gluon field configurations and HISQ…

High Energy Physics - Lattice · Physics 2024-01-29 Judd Harrison , Christine T. H. Davies

We present recent updates for $\varepsilon_K$ determined directly from the standard model (SM) with lattice QCD inputs such as $\hat{B}_K$, $|V_{cb}|$, $|V_{us}|$, $\xi_0$, $\xi_2$, $\xi_\text{LD}$, $f_K$, and $m_c$. We find that the…

High Energy Physics - Lattice · Physics 2023-02-07 Sunghee Kim , Sunkyu Lee , Weonjong Lee , Jaehoon Leem , Sungwoo Park

We extract the Cabibbo-Kobayashi-Maskawa matrix element $V_{cb}$ from the exclusive decays of $\Lambda_b\to \Lambda_c\ell\bar \nu_\ell$ and $\Lambda_b\to \Lambda_c M_{(c)}$ with $M=(\pi^-,K^-)$ and $M_c=(D^-,D^-_s)$, where the branching…

High Energy Physics - Phenomenology · Physics 2017-11-02 Y. K. Hsiao , C. Q. Geng

We determine $|V_{cb}|$ from inclusive semileptonic B decays including resummation of supposedly large perturbative corrections, which originate from the running of the strong coupling. We argue that the low value of the BLM scale found…

High Energy Physics - Phenomenology · Physics 2007-05-23 Patricia Ball

The precise determination of the CKM elements $V_{cb}$ and $V_{ub}$ is crucial for any new physics analysis in the flavour sector. Their values can be determined from several tree-level decays: $V_{cb}$ can be extracted from $B\to D\ell\nu$…

High Energy Physics - Phenomenology · Physics 2015-01-14 Andreas Crivellin , Stefan Pokorski

In light of the large amount of new experimental data, we revisit the determination of V_{cb} and m_b from inclusive semileptonic and radiative B decays. We study shape variables to order lqcd^3/m_b^3 and alpha_s^2\beta_0, and include the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Christian W. Bauer , Zoltan Ligeti , Michael Luke , Aneesh V. Manohar , Michael Trott

We present an updated determination of the values of $\vert V_{cb} \vert$, $R(D^*)$ and $\vert V_{ub} \vert/\vert V_{cb} \vert$ based on the new data on semileptonic $B \to D^* \ell \nu_\ell$ decays by the Belle and Belle-II Collaborations…

High Energy Physics - Phenomenology · Physics 2024-03-26 G. Martinelli , S. Simula , L. Vittorio
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