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Related papers: Shape Function Effects in B -> X_c l \nu_l

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In the heavy quark limit, the form factors for semileptonic and rare radiative B decays into light mesons are related by heavy quark spin symmetry. Here we compute the leading corrections of order \Lambda/m_Q to these symmetry relations,…

High Energy Physics - Phenomenology · Physics 2009-11-07 Benjamin Grinstein , Dan Pirjol

We resum to next-to-leading order the distribution in the ratio of the invariant hadron mass mX to the total hadron energy EX and the distribution in mX in the semileptonic decays B -> Xu l nu. By expanding our formulas, we obtain the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ugo Aglietti , Giulia Ricciardi , Giancarlo Ferrera

We derive a new parton-like formula, which establishes a simple connection between the electroweak decay rate $\Gamma (\bar B \to X_s\gamma$) and the rate of a free b-quark decay. The main features of our approach are the treatment of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Y. -Y. Keum , P. Yu. Kulikov , I. M. Narodetskii , H. S. Song

A recent calculation by Chay and Rey has shown that instantons may make a significant contribution to the lepton energy spectrum near its endpoint. Using an ansatz borrowed from the study of high energy baryon number violating processes, we…

High Energy Physics - Phenomenology · Physics 2010-11-01 Adam F. Falk , Alexander Kyatkin

The form factors of the semileptonic $B$, $B_s$ and $B_c$ meson decays are calculated in the framework of the relativistic quark model based on the quasipotential approach in QCD. They are expressed through the overlap integrals of the…

High Energy Physics - Phenomenology · Physics 2022-07-27 R. N. Faustov , V. O. Galkin , Xian-Wei Kang

We estimate the heavy quark effective theory parameter \lambda_1 from inclusive semileptonic B-meson decay spectrum. By using recent CLEO double lepton tagging data of B -> X e nu, which shows the lepton momentum as low as 0.6 GeV, we…

High Energy Physics - Phenomenology · Physics 2011-01-27 K. K. Jeong , C. S. Kim

We present an investigation of the lepton energy distributions in the inclusive semileptonic weak decays of heavy baryons performed within a relativistic quark model formulated on the light front (LF). Using the heavy-quark LF distribution…

High Energy Physics - Phenomenology · Physics 2008-11-26 I. D'Souza , C. S. Kalman , P. Yu. Kulikov , I. M. Narodetskii

We analyze the end-point region of the photon spectrum in semi-inclusive radiative decays of very heavy quarkonium (m alpha_s^2 >> Lambda_QCD). The S- and P-wave octet shape functions are calculated. When they are included in the analysis…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xavier Garcia i Tormo

The hadronic invariant mass spectrum for the inclusive charmless semileptonic decay $B\to X_u e \bar\nu_e$ is studied. Particular attention is paid to the region $s_H<m_D^2$, which may be useful for extracting the value of $|V_{ub}|$. The…

High Energy Physics - Phenomenology · Physics 2014-11-17 Adam F. Falk , Zoltan Ligeti , Mark B. Wise

In this talk, we review the QCD calculation of the lepton spectrum from inclusive semileptonic $B$ decay. We compare this prediction to that of the ACCMM model. This latter work was done in collaboration with Csaba Csaki.

High Energy Physics - Phenomenology · Physics 2015-06-25 Lisa Randall

The inclusive spectra of radiative and semi-leptonic B-meson decays near the endpoint is computed taking into account renormalons in the Sudakov exponent (Dressed Gluon Exponentiation). In this framework we demonstrate the factorization of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Einan Gardi

We demonstrate, by an explicit one-loop calculation, that at leading twist the nonperturbative effects in B -> gamma l nu, B -> gamma gamma and B -> gamma l+ l- radiative decays are contained in a common multiplicative factor…

High Energy Physics - Phenomenology · Physics 2009-10-09 S. Descotes-Genon , C. T. Sachrajda

We present a new approach to the analysis of quark-binding effects in inclusive decays of heavy mesons within the relativistic dispersion quark model. Various differential distributions, such as electron energy spectrum, $q^2$- and…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Melikhov , S. Simula

The decay of B mesons can be predicted within the Heavy Quark Expansion as the decay of a free bottom quark plus corrections which are suppressed by powers of $1/m_b$. This contribution to Loops&Legs 2024 describes the calculation of the…

High Energy Physics - Phenomenology · Physics 2024-07-02 Manuel Egner

The inclusive and exclusive semileptonic decay distributions for b -> c decay are computed in the Shifman-Voloshin limit. The inclusive decay distributions (computed using an operator product expansion) depend on quark masses, and the…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. Glenn Boyd , Benjamin Grinstein , Aneesh V. Manohar

We report measurements of the inclusive electron energy spectrum and hadron invariant mass spectrum for charmed semileptonic decays of B mesons in a 140 fb^-1 data sample collected with the Belle detector at the KEKB e+e- collider. We…

High Energy Physics - Experiment · Physics 2019-08-14 Phillip Urquijo

Measuring the photon energy spectrum in radiative B decays provides essential help for gaining theoretical control over semileptonic B transitions. The hadronic recoil mass distribution in B -> X_u \ell\nu promises the best environment for…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ikaros Bigi , Nikolai Uraltsev

The hadronic form factors of $B_c$ semileptonic decays to the $P-$wave charmonium 4-plet can be expressed near the zero-recoil point in terms of universal functions, performing a systematic expansion in QCD in the relative velocity of the…

High Energy Physics - Phenomenology · Physics 2022-11-23 P. Colangelo , F. De Fazio , N. Losacco , F. Loparco , M. Novoa-Brunet

We derive precise standard model predictions for the dilepton invariant mass and the tau energy distributions in inclusive B -> Xc tau nu decay. We include Lambda_QCD^2/m_b^2 and alpha_s corrections using the 1S short-distance mass scheme,…

High Energy Physics - Phenomenology · Physics 2014-09-05 Zoltan Ligeti , Frank J. Tackmann

We summarize recent results on QCD corrections to various observables in semileptonic $b$ quark decays. For massless leptons in the final state we present effects of such corrections on triple differential distribution of leptons which are…

High Energy Physics - Phenomenology · Physics 2016-09-01 Andrzej Czarnecki , Marek Jezabek