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

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The heavy quark effective theory makes model independent predictions for semileptonic $\Lambda_b \to \Lambda_c$ decays in terms of a small set of parameters. No subleading Isgur-Wise function occurs at order $\Lambda_{\rm QCD}/m_{c,b}$, and…

High Energy Physics - Phenomenology · Physics 2018-11-21 Florian U. Bernlochner , Zoltan Ligeti , Dean J. Robinson , William L. Sutcliffe

We propose a method for a QCD based calculation of one-particle inclusive decays of the form B \to \bar D X or B \to \bar D^* X. It is based on the heavy mass limit and a short distance expansion of the amplitudes, which yield a power…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. Balzereit , T. Mannel

The shape of the lepton spectrum in inclusive semileptonic $B\to X\,\ell\,\bar\nu_\ell$ decay is sensitive to matrix elements of the heavy quark effective theory, $\bar\Lambda$ and $\lambda_1$. From CLEO data we extract…

High Energy Physics - Phenomenology · Physics 2014-11-17 Martin Gremm , Anton Kapustin , Zoltan Ligeti , Mark B. Wise

We apply a recent theoretical analysis of hadronic observables in inclusive semileptonic heavy hadron decays to the phenomenology of $B$ and $D$ mesons. Correlated bounds on the nonperturbative parameters $\bar\Lambda$ and $\lambda_1$ are…

High Energy Physics - Phenomenology · Physics 2014-11-17 Adam F. Falk , Michael Luke , Martin J. Savage

We present a QCD sum-rule determination of the heavy-quark kinetic energy inside a heavy meson, $-\lambda_1/2 m_Q$, which is consistent with the field-theory analog of the virial theorem. We obtain $-\lambda_1\approx (0.10\pm…

High Energy Physics - Phenomenology · Physics 2009-10-28 Matthias Neubert

We address the nonperturbative effects associated with soft charm quarks in inclusive B decays. Such corrections are allowed by the OPE, but have largely escaped attention so far. The related four-quark `double heavy' expectation values of…

High Energy Physics - Phenomenology · Physics 2008-11-26 I. I. Bigi , N. Uraltsev , R. Zwicky

Semileptonic B decays are described by the Isgur-Wise form factor to the leading order in 1/m; four new functions appear in the first order [Luke]. Values of these functions are crucial for the applicability of the whole approach to…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. N. Baier , A. G. Grozin

Applying an operator product expansion approach we update the Standard Model prediction of the $B_c$ lifetime from over 20 years ago. The non-perturbative velocity expansion is carried out up to third order in the relative velocity of the…

High Energy Physics - Phenomenology · Physics 2021-08-04 Jason Aebischer , Benjamín Grinstein

Decays of the fully beauty four-quark structures $X_{\mathrm{4b}}$ and $T_{ \mathrm{4b}}$ to $B$ meson pairs are investigated in the framework of QCD three-point sum rule method. We model the scalar exotic mesons $X_{\mathrm{4b }}$ and…

High Energy Physics - Phenomenology · Physics 2024-01-03 S. S. Agaev , K. Azizi , B. Barsbay , H. Sundu

We develop the perturbative QCD formalism for inclusive semileptonic $B$ meson decays, which includes Sudakov suppression from the resummation of large radiative corrections near the high end of charged lepton energy. Transverse degrees of…

High Energy Physics - Phenomenology · Physics 2014-11-17 Hsiang-nan Li , Hoi-Lai Yu

We present some straightforward applications of the QCD heavy quark expansion, stated in previous papers [1-3], to the inclusive widths of heavy flavour hadrons. We address the question of the $D_s$ lifetime and argue that -- barring Weak…

High Energy Physics - Phenomenology · Physics 2010-11-01 I. I. Bigi , N. G. Uraltsev

The $\b$ decay does not receive any nonspectator contributions and hence its theoretical calculation is relatively clean. Two different methods are employed for the study of $\b$. In the first method, both $b$ and $s$ quarks are treated as…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hai-Yang Cheng , B. Tseng

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 study the color-allowed $\Lambda_b\rightarrow \Lambda_c \pi, \Lambda_cK$ decays in the perturbative QCD approach (PQCD) to lowest order in strong coupling constant $\alpha_s$. Both the factorizable and nonfactorizable contributions are…

High Energy Physics - Phenomenology · Physics 2022-04-26 Chao-Qi Zhang , Jia-Ming Li , Meng-Kun Jia , Zhou Rui

We consider the effects of quark-binding on the angular distribution and polarization characteristics of the inclusive decays $\Lambda_b \to X_s \gamma$ and $\Lambda_b \to X_c l \bar{\n}_l$ $(l=e, \tau)$, using the methods of heavy quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Gremm , G. Köpp , F. Krüger , L. M. Sehgal

In this talk I give an introduction to methods used to give a model independent description of QCD effects in B-decays. I discuss three useful expansions: mb/mW << 1 for the electroweak Hamiltonian, LambdaQCD/mb << 1 for Heavy Quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 Iain W. Stewart

We compute the QCD corrections to the decay rate difference in the $B_s-\bar B_s$ system, $\Delta\Gamma_{B_s}$, in the next-to-leading logarithmic approximation using the heavy quark expansion approach. Going beyond leading order in QCD is…

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

The problem of the $\Xi_{c}^{+}$ lifetime is considered in the framework of {\em Heavy-Quark Expansion} and $SU(3)_{flavor}$ symmetry. The lifetime of $\Xi_{c}^{+}$ is expressed in terms of measurable inclusive quantities of the other two…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. Guberina , H. Stefancic

The $\Lambda_b \to p$ semileptonic decay is analyzed by using QCD sum rules within the framework of heavy quark effective theory. The Isgur-Wise function of $\Lambda_b \to p l \bar\nu$ has been calculated. The decay width is given.

High Energy Physics - Phenomenology · Physics 2009-10-31 Chao-Shang Huang , Cong-Feng Qiao , Hua-Gang Yan

A recently proposed approach to compute the inclusive semi-leptonic decay rate on the lattice allows for the calculation of various quantities (differential distributions and moments) in different subchannels. We systematically compare the…

High Energy Physics - Phenomenology · Physics 2021-11-05 Paolo Gambino , Shoji Hashimoto , Sandro Mächler