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

200 papers

We reduce the perturbative uncertainty in the determination of |V_{ub}| from inclusive semileptonic B decays by calculating the rate of B -> X_u l nu events with dilepton invariant mass q^2>(M_B-M_D)^2 at subleading order in the hybrid…

High Energy Physics - Phenomenology · Physics 2014-11-17 Matthias Neubert , Thomas Becher

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…

Using BaBar measurements of the inclusive electron spectrum in B->X_u e nu decays and the inclusive photon spectrum in B->X_s gamma decays, we extract the magnitude of the CKM matrix element Vub. The extraction is based on theoretical…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. B. Golubev , V. G. Luth , Yu. I. Skovpen

We propose a method of extracting the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ from two-body hadronic decay processes of $B\to DK$ with precisely determined form factors of $B$ meson semi-leptonic decays. The amplitude…

High Energy Physics - Phenomenology · Physics 2019-12-06 Noriaki Kitazawa , Kyo-suke Masukawa , Yuki Sakai

We report the recent progress from our group in extracting observables of both inclusive and exclusive semileptonic heavy-meson decays directly from lattice QCD four-point correlators. On the inclusive side, we illustrate how to estimate…

High Energy Physics - Lattice · Physics 2026-01-15 Zhi Hu , Alessandro Barone , Ahmed Elgaziari , Shoji Hashimoto , Andreas Jüttner , Takashi Kaneko , Ryan Kellermann

We report measurements of partial branching fractions for inclusive charmless semileptonic B decays Bbar --> Xu l nubar, and the determination of the CKM matrix element |V_{ub}|. The analysis is based on a sample of 467 million Upsilon(4S)…

High Energy Physics - Experiment · Physics 2013-05-30 The BABAR Collaboration

An overview of experimental determinations of different CKM elements is given with an emphasis on |Vub| and |Vcb| extraction. Measurements are compared to the Standard Model predictions and constraints on the unitarity triangle, arising…

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

We reemphasize the strong dependence of the branching ratios $B(K^+\to\pi^+\nu\bar\nu)$ and $B(K_L\to\pi^0\nu\bar\nu)$ on $|V_{cb}|$ that is stronger than in rare $B$ decays, in particular for $K_L\to\pi^0\nu\bar\nu$. Thereby the persistent…

High Energy Physics - Phenomenology · Physics 2022-06-03 Andrzej J. Buras , Elena Venturini

We have extracted the ratio $|V_{ub}|/|V_{cb}|$ from a combined study of the available inputs on $\bar{B}\to (\pi,\rho,\omega)\ell^- \bar{\nu}_{\ell}$ and $\bar{B}(\bar{B}_s)\to (D^{(\ast)}, D_s^{(\ast)})\ell^- \bar{\nu}_{\ell}$ ($\ell =…

High Energy Physics - Phenomenology · Physics 2023-07-26 Aritra Biswas , Soumitra Nandi , Ipsita Ray

We present a study on the nonperturbative calculation of observables for inclusive semileptonic decays of $B_{(s)}$ mesons using lattice QCD. We focus on the comparison of two different methods to analyse the lattice data of Euclidean…

High Energy Physics - Lattice · Physics 2024-01-01 Alessandro Barone , Shoji Hashimoto , Andreas Jüttner , Takashi Kaneko , Ryan Kellermann

Unitarity along with precision measurements of sin2\beta, V_{us} and V_{cb} allows one to find a lower bound V_{ub}\geq 0.0035 which, on using the recently measured angle \alpha of the unitarity triangle, translates to V_{ub}= 0.0035\pm…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gulsheen Ahuja , Manmohan Gupta , Sanjeev Kumar , Monika Randhawa

We explore the theoretical feasibility of extracting V_ub from two ratios built from B meson inclusive partial decays, R_1 = Gamma(b-> u cbar s)/3Gamma(b -> c l nu), and R_2 = [Gamma(b -> c X) - Gamma(b -> cbar X)]/Gamma(b -> c ubar d). We…

High Energy Physics - Phenomenology · Physics 2010-11-23 Junegone Chay , Adam F. Falk , Michael Luke , Alexey A. Petrov

We use Omnes representations of the form factors V, A_1 and A_2 for exclusive semileptonic B--> rho decays, and apply them to combine experimental partial branching fraction information with theoretical calculations of the three form…

High Energy Physics - Phenomenology · Physics 2010-11-19 Jonathan M Flynn , Yoshiyuki Nakagawa , Juan Nieves , Hiroshi Toki

We review recent experimental and theoretical developments in inclusive semileptonic B -> Xc l nu decays. In particular, we discuss the determination of |Vcb| and of the heavy quark masses through fits based on the Operator Product…

High Energy Physics - Experiment · Physics 2011-02-02 Paolo Gambino , Christoph Schwanda

We present a non-perturbative computation of inclusive rates of semileptonic decays of heavy mesons from lattice QCD simulations. The calculation is based on the extraction of smeared spectral functions obtained from four-point Euclidean…

We report a measurement of the inclusive charmless semileptonic branching fraction of B mesons in a sample of 89 million BBbar events recorded with the BABAR detector at the Y(4S) resonance. Events are selected by fully reconstructing the…

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

Recently several papers extracted $|V_{cb}|$ using the Belle measurement of the exclusive $\bar B \to D^* \ell\bar\nu$ unfolded differential decay rates, available for the first time. Depending on the theoretical inputs, some of the fits…

High Energy Physics - Phenomenology · Physics 2017-11-22 Florian U. Bernlochner , Zoltan Ligeti , Michele Papucci , Dean J. Robinson

Charmless semileptonic decays, ${\bar{B}} \to X_u \ell \bar{\nu}$, are studied in a sample of 232 million $B\bar{B}$ decays recorded with the BaBar detector, in events where the decay of the second $B$ meson is fully reconstructed.…

High Energy Physics - Experiment · Physics 2016-08-31 B. Aubert , BABAR Collaboration

In the framework of a relativistic covariant Bethe-Salpeter model for the quark-antiquark system we present a renewed determination of the Cabbibo-Kobayashi-Maskawa matrix element $|V_{cb}|$. Complementing an earlier analysis applied to the…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Beyer

A precise determination of |V_{ub}| can be obtained exploiting the sum rule for inclusive charmless semileptonic B-meson decays. The sum rule is derived on the basis of light-cone expansion and b-flavored quantum number conservation. The…

High Energy Physics - Phenomenology · Physics 2009-10-31 Changhao Jin