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Related papers: |V_{cb}| from semileptonic B decays with two-loop …

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B decay sum rules relate exclusive B semileptonic decay matrix elements to forward B-meson matrix elements of operators in HQET. At leading order the operators that occur are the b-quark kinetic energy $\lambda_1$ and chromomagnetic energy…

High Energy Physics - Phenomenology · Physics 2009-10-30 Mark B. Wise

We show -- by explicit computation of first-order corrections -- that the QCD factorization approach previously applied to hadronic two-body decays and to form factor ratios also allows us to compute non-factorizable corrections to…

High Energy Physics - Phenomenology · Physics 2010-03-26 M. Beneke , Th. Feldmann , D. Seidel

We use a multiply-subtracted Omnes dispersion relation for the form factor f^+ in B->pi semileptonic decay, allowing the direct input of experimental and theoretical information to constrain its dependence on q^2. Apart from these inputs we…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jonathan M Flynn , Juan Nieves

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

Two-gluon radiative corrections to the $b\to c\ell\nu$ decay width have been computed analytically as an expansion in terms of \frac{m_c}{m_b} << 1 in the kinematical limit of zero lepton invariant mass. The obtained results match smoothly…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Pak , I. Blokland , A. Czarnecki

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 present the results of a calculation of the perturbative QCD corrections for the semileptonic inclusive width of a heavy flavored meson. Within the Heavy Quark Expansion we analytically compute the QCD correction to the coefficient of…

High Energy Physics - Phenomenology · Physics 2015-03-30 Thomas Mannel , Alexei A. Pivovarov , Denis Rosenthal

Pade-approximant methods are used to estimate the three-loop perturbative contributions to the inclusive semileptonic $b \to u$ decay rate. These improved estimates of the decay rate reduce the theoretical uncertainty in the extraction of…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. G. Steele , M. R. Ahmady , F. A. Chishtie , V. Elias

I present two recent pieces of work on semileptonic $B \to \pi, \rho$ decays where it is shown how lattice QCD calculations can be used to test heavy-quark symmetry and determine phenomenologically relevant quantities despite the limits on…

High Energy Physics - Phenomenology · Physics 2009-10-28 Laurent Lellouch

We study the triple differential distribution of B-> Xu l nu, consistently including all perturbative and non-perturbative effects through O(alphas^2 beta_0) and O(1/mb^3). The Fermi motion is parameterized in terms of a single light-cone…

High Energy Physics - Phenomenology · Physics 2009-02-18 P. Gambino , P. Giordano , G. Ossola , N. Uraltsev

In this paper we compute $\alpha_s$ corrections to the matching coefficients of the dimension six operators in the Heavy Quark Expansion of the inclusive semileptonic heavy hadron decay rate and leptonic invariant mass spectrum with a…

High Energy Physics - Phenomenology · Physics 2024-03-04 Daniel Moreno

In these lectures I review what has been learned from studies of b-quark decays, including semileptonic decays ($V_{ub}$ and $V_{cb}$), $B^o-\overline{B}^o$ mixing and rare B decays. Then a discussion on CP violation follows, which leads to…

High Energy Physics - Phenomenology · Physics 2014-11-17 Sheldon Stone

Applications of QCD factorization to $B\to\phi K$, charmless $B\to VV$, $B\to J/\psi K(K^*)$ and semi-inclusive decays $B\to MX$ are discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 Hai-Yang Cheng

We consider the isospin breaking corrections to charmless semileptonic decays of B mesons. Both, the recently measured branching ratios of exclusive decays by the CLEO Collaboration and the end-point reion of the inclusive lepton spectrum…

High Energy Physics - Phenomenology · Physics 2010-11-23 G. Lopez Castro , J. H. Munoz , G. Toledo Sanchez

The semileptonic decay B->pi is studied starting from a simple quark model and taking into account the effect of the B* resonance. A novel, multiply subtracted, Omn\`es dispersion relation has been implemented to extend the predictions of…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Albertus , J. M. Flynn , E. Hernandez , J. Nieves , J. M. Verde--Velasco

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

A brief report on the QCD factorization approach to exclusive B decays and its applications is presented. In an appendix a subtle issue concerning partial integration in the parameterization of infrared-sensitive power corrections is…

High Energy Physics - Phenomenology · Physics 2011-01-27 M. Beneke

We calculate the electron spectrum of semileptonic decays of B-mesons into non-charmed hadrons. The shape of the spectrum obtained from QCD sum rules is in general agreement with quark model calculations. At high electron energies the…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Ball , V. M. Braun , H. G. Dosch

The semileptonic $B_s (B) \to K_2^*(a_2, f_2) \ell\nu$, $\ell=\tau, \mu$ transitions are investigated in the frame work of the three-point QCD sum rules. Considering the quark condensate contributions, the relevant form factors of these…

High Energy Physics - Phenomenology · Physics 2018-04-17 R. Khosravi , S. Sadeghi

We derive a new parton formula for the inclusive B decays and briefly discuss its applications to semileptonic and weak radiative decays of the B-meson.

High Energy Physics - Phenomenology · Physics 2011-01-25 S. Kotkovsky , I. M. Narodetskii , K. A. Ter-Martirosyan , S. Simula