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Related papers: Shape Functions from B -> X_c \ell \nu

200 papers

Inclusive semileptonic decays of beauty baryons are studied using the heavy quark expansion to ${\cal O}(1/m_b^3)$, at leading order in $\alpha_s$. The case of a polarized decaying baryon is examined, with reference to $\Lambda_b$. An…

High Energy Physics - Phenomenology · Physics 2022-12-19 Pietro Colangelo , Fulvia De Fazio , Francesco Loparco

A new estimate is presented of the dileptonic $B$ decays $B\to\pi\ell^+\ell^-(\ell=e,\mu,\tau)$ in naive factorization within the standard-model (SM) framework. Using a combination of several approaches, we investigate the behavior of the…

High Energy Physics - Phenomenology · Physics 2014-11-11 Zuo-Hong Li , Zong-Guo Si , Ying Wang , Nan Zhu

The inclusive decay rate b to ccs is enhanced considerably due to perturbative QCD corrections. We recalculate the dominant part of the NLO-QCD corrections, because they cannot be reconstructed from the literature and we give the full…

High Energy Physics - Phenomenology · Physics 2015-06-16 Fabian Krinner , Alexander Lenz , Thomas Rauh

It is argued that the dominant subleading shape-function contributions to the endpoint region of the charged-lepton energy spectrum in B -> X_u l nu decays can be related in a model-independent way to an integral over the B -> X_s gamma…

High Energy Physics - Phenomenology · Physics 2010-04-05 Matthias Neubert

We derive a class of formulae relating moments of B -> Xu l nu to B -> Xs gamma in the shape function region, where m_X^2 ~ m_b Lambda_QCD. We also derive an analogous class of formulae involving the decay B -> Xs l+ l-. These results…

High Energy Physics - Phenomenology · Physics 2008-12-16 Keith S. M. Lee

The differential decay spectrum $d\Gamma/dE_e dq^2$ for the semileptonic decay of an unpolarized hadron containing a b-quark, and the decay spectrum $d\Gamma/dE_e dq^2 d\!\cos\theta$ for polarized $\Lambda_b$ decay are computed to second…

High Energy Physics - Phenomenology · Physics 2010-11-01 Aneesh V. Manohar , Mark B. Wise

The transition form factors describing the semileptonic decays of heavy pseudoscalar mesons are investigated within a relativistic constituent quark model formulated on the light-front. For the first time, the form factors are calculated in…

High Energy Physics - Phenomenology · Physics 2009-10-28 I. L. Grach , I. M. Narodetskii , S. Simula

We calculate semileptonic form factors for the decays $B_c \to \eta_c \, l \nu$ and $B_c \to J/\psi \, l \nu$ over the entire $q^2$ range, using a highly improved lattice quark action for charm at several lattice spacings down to $a=0.045$…

High Energy Physics - Lattice · Physics 2016-11-08 Brian Colquhoun , Christine Davies , Jonna Koponen , Andrew Lytle , Craig McNeile

We analyze the inclusive semileptonic $B \to X_c \ell\nu$ structure functions in 2+1-flavor lattice QCD. The M\"obius domain-wall fermion action is used for light, strange, charm and bottom quarks. The structure function receives…

High Energy Physics - Lattice · Physics 2020-02-03 G. Bailas , S. Hashimoto , T. Kaneko , J. Koponen

We perform a non-perturbative lattice calculation of the decay rates for inclusive semi-leptonic decays of charmed mesons. In view of the long-standing tension in the determination of the CKM matrix elements $|V_{ub}|$ and $|V_{cb}|$ from…

High Energy Physics - Lattice · Physics 2022-12-01 Ryan Kellermann , Alessandro Barone , Shoji Hashimoto , Andreas Jüttner , Takashi Kaneko

In this article, we calculate the $B_c^* \to \eta_c$ form-factors with the three-point QCD sum rules, then study the semileptonic decays $B_c^* \to \eta_c \ell \bar{\nu}_{\ell}$. The tiny decay widths may be observed experimentally in the…

High Energy Physics - Phenomenology · Physics 2013-12-25 Zhi-Gang Wang

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

We calculate the decay distributions for inclusive B -> X_s gamma and B -> X_u l nu decays in the endpoint region, where radiative corrections are large. The computation is done using effective field theory methods. The matching…

High Energy Physics - Phenomenology · Physics 2011-05-05 Christian W. Bauer , Aneesh V. Manohar

In the covariant light-front quark model, we investigate the form factors of $B_c$ decays into $D, D^*, D_s, D_s^*, \eta_c, J/\psi, B, B^*, B_s, B_s^*$ mesons. The form factors in the spacelike region $q^2<0$ are directly evaluated. To…

High Energy Physics - Phenomenology · Physics 2014-11-18 Wei Wang , Yue-Long Shen , Cai-Dian Lü

I report results in semileptonic decays of B mesons from the CLEO collaboration, with a focus on recent results. Results for exclusive reconstruction of B -> D* l nu, B -> D l nu and B -> rho l nu are given including the q^2 dependence of…

High Energy Physics - Experiment · Physics 2009-10-31 Karl M. Ecklund

Semileptonic $B_s \to K \ell \nu$ decays provide an alternative $b$-decay channel to determine the CKM matrix element $|V_{ub}|$, and to obtain a $R$-ratio to investigate lepton-flavor-universality violations. Results for the CKM matrix…

High Energy Physics - Lattice · Physics 2023-06-21 Jonathan M. Flynn , Ryan C. Hill , Andreas Jüttner , Amarjit Soni , J. Tobias Tsang , Oliver Witzel

We investigate the semileptonic decays $\Lambda_{b} \to \Lambda_{c} \ell^- \bar{\nu}_\ell$ (with $\ell = e, \mu, \tau$) within the framework of perturbative QCD (pQCD). The six independent $\Lambda_b \to \Lambda_c$ transition form factors…

High Energy Physics - Phenomenology · Physics 2025-09-03 Ying Li , Jie Chen , Ya-Xin Wang , Zhi-Tian Zou

In the framework of three-point QCD sum rules, the form factors for the semileptonic decays of B_c^+ -> B_s(B_s^*) l \nu are calculated with account for the Coulomb-like alpha_s/v-corrections in the heavy quarkonium. The generalized…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. V. Kiselev , A. E. Kovalsky , A. K. Likhoded

Quantum chromodynamics (QCD) effects in the semileptonic decay b -> c l nu are evaluated to the second order in the coupling constant, O(alpha_s^2), and to several orders in the expansion in quark masses, m_c/m_b. Corrections are calculated…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alexey Pak , Andrzej Czarnecki

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