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Related papers: On the Theoretical Understanding of Inclusive $\La…

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In this paper, we evaluate the expectation values of four-quark operators for the inclusive beauty decays from the differences in the inclusive total decay rates, assuming that the heavy quark expansion converges at $O(1/m^3)$. The obtained…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Arunagiri

A possible explanation of the apparent disrepency between the theoretical prediction and experimental measurement of the ratio of lifetimes $\tau(\Lambda_b)/\tau(B_d)$ is that ``spectator effects'', which appear at $O(1/m_b^3)$ in the heavy…

High Energy Physics - Lattice · Physics 2008-11-26 Massimo Di Pierro , Chris T Sachrajda , Chris Michael

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

I identify a source of Lambda_{QCD}/m_Q corrections to the assumption of quark-hadron duality in the application of heavy quark methods to inclusive heavy quark semileptonic decays Q->q l nu_l. These corrections could substantially affect…

High Energy Physics - Phenomenology · Physics 2007-05-23 Nathan Isgur

It has recently been pointed out that a new class of subleading shape functions involving B-meson matrix elements of non-local four-quark operators contributes at order Lambda_{QCD}/m_b to B->X_u+l+nu decay distributions in the endpoint…

High Energy Physics - Phenomenology · Physics 2009-01-07 Matthias Neubert

We compute perturbative QCD corrections to the lifetime splitting between the charged and neutral $B$ meson in the framework of the heavy quark expansion. These next-to-leading logarithmic corrections are necessary for a meaningful use of…

High Energy Physics - Phenomenology · Physics 2009-10-09 M. Beneke , G. Buchalla , C. Greub , A. Lenz , U. Nierste

We discuss nonperturbative contributions to the inclusive rare $B$ decays $B\to X_s\gamma$ and $B\to X_s\ell^+\ell^-$. We employ an operator product expansion and the heavy quark effective theory to compute the leading corrections to the…

High Energy Physics - Phenomenology · Physics 2009-10-22 Adam F. Falk , Michael Luke , Martin J. Savage

The decay constants of the pseudoscalar mesons B and B_s are evaluated from QCD sum rules for the pseudoscalar two-point function. Recently calculated perturbative three-loop QCD corrections are incorporated into the sum rule. An analysis…

High Energy Physics - Phenomenology · Physics 2011-05-05 Matthias Jamin , Bjorn O. Lange

Phenomenological models of heavy flavour decays differ significantly in their predictions of global features of $B_c$ decays, like the $B_c$ lifetime or the relative weight of $c\ra s$ and $b\ra c$ transitions. The $1/m_Q$ expansion which…

High Energy Physics - Phenomenology · Physics 2009-10-28 I. I. Bigi

I discuss the heavy quark expansion for the inclusive widths of heavy-light hadrons, which predicts quite well the experimental ratios of B_q meson lifetimes. As for $\Lambda_b$, current determinations of ${\cal O}(m_b^{-3})$ contribution…

High Energy Physics - Phenomenology · Physics 2008-11-26 Fulvia De Fazio

With only the tree level operator, the decay of $\Lambda_b\rightarrow pK$ is predicted to be one order smaller than the experimental data. The QCD penguin effects should be taken into account. In this paper, we explore the one-loop QCD…

High Energy Physics - Phenomenology · Physics 2016-06-22 Jie Zhu , Hong-Wei Ke , Zheng-Tao Wei

We show that threshold resummation of the end-point logarithms in inclusive $b$-hadron decays leads to a Sudakov factor, which introduces $1/m_b$ power corrections through infrared renormalons. These power corrections are strong enough to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Huei-Shih Liao , Hsiang-nan Li

The Lambda_b to Lambda_c semileptonic decay is analyzed in the framework of heavy quark effective theory to the order of 1/m_c and 1/m_b. The QCD sum rule and large N_c predictions to the decay form factors are applied. It argues that the…

High Energy Physics - Phenomenology · Physics 2011-01-27 Jong-Phil Lee , Chun Liu , H. S. Song

We present an analytical calculation of the $\alpha_s$ corrections for the coefficient of $\rho_D/m_Q^3$ term in the heavy quark expansion for the inclusive semileptonic decays of heavy hadrons, such as $B \to X_c \ell \bar{\nu}$. The full…

High Energy Physics - Phenomenology · Physics 2019-11-20 Thomas Mannel , Alexei A. Pivovarov

We present the theory of inclusive decays of hadrons containing a heavy quark and discuss its most important applications to the decays of B mesons. We also review the theoretical understanding of the hadronic parameters lambda_1 and…

High Energy Physics - Phenomenology · Physics 2014-11-17 Matthias Neubert

The matrix element of the weak transition {\Lambda}_b\rightarrow{\Lambda}_c can be expressed in terms of six form factors. {\Lambda}_Q(Q = b;c) can be regarded as composed of a heavy quark Q(Q = b;c) and a diquark which is made up of the…

High Energy Physics - Phenomenology · Physics 2016-08-17 L. Zhang , X. -H. Guo , M. -H. Weng

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

Taking into account the $\Lambda$ baryon distribution amplitudes and the most general form of the interpolating current of the $\Lambda_{b}$, the semileptonic $\Lambda_{b}\rar \Lambda \ell^+\ell^- $ transition is investigated in the…

High Energy Physics - Phenomenology · Physics 2010-05-19 T. M. Aliev , K. Azizi , M. Savci

We present a model-independent study of spectator effects, which are responsible for the lifetime differences between beauty hadrons. These effects can be parametrized in terms of hadronic matrix elements of four four-quark operators. For…

High Energy Physics - Phenomenology · Physics 2009-10-09 M. Neubert , C. T. Sachrajda

We apply the new formulation of heavy quark effective field theory (HQEFT) to the inclusive decays of bottom hadrons. The long-term ambiguity of using heavy quark mass or heavy hadron mass for inclusive decays is clarified within the…

High Energy Physics - Phenomenology · Physics 2016-12-28 Y. A. Yan , Y. L. Wu , W. Y. Wang