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Related papers: Rare dileptonic decays of \Lambda_b in a quark mod…

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We investigate the rare decay $\Lambda_b \to \Lambda \gamma$ which receives both short and long distance contributions. We estimate the long distance contributions and find them very small. The form factors are obtained from $\Lambda_c \to…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Mannel , S. Recksiegel

We present results of the first lattice QCD calculations of the weak matrix elements for the decays $B_c^+ \to D^0 \ell^+ \nu_{\ell}$, $B_c^+ \to D_s^+ \ell^+ \ell^-$ and $B_c^+ \to D_s^+ \nu \overline{\nu}$. Form factors across the entire…

High Energy Physics - Lattice · Physics 2021-11-15 Laurence Cooper , Christine Davies , Matthew Wingate

In a covariant quark-diquark model, we investigate the rare decay of $\Lambda_b \rightarrow n l^+ l^-$ and $\Lambda_b \rightarrow n \gamma$ in the Bethe-Salpeter equation approach. In this model the baryons are treated as bound states of a…

High Energy Physics - Phenomenology · Physics 2020-03-10 Liang-Liang Liu , Chao Wang , Xian-Wei Kang , Xin-Heng Guo

Semileptonic and nonleptonic decays of the B_c meson are studied in the framework of the relativistic quark model. The heavy quark expansion in inverse powers of the heavy (b,c) quark mass is used to simplify calculations while the light…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Ebert , R. N. Faustov , V. O. Galkin

The energetic exclusive two-body nonleptonic decays of B mesons are investigated in the framework of the relativistic quark model within the factorization approximation. The heavy quark expansion is used for the calculation of form factors.…

High Energy Physics - Phenomenology · Physics 2011-08-17 D. Ebert , R. N. Faustov , V. O. Galkin

A study of the decay channels Lambda_{b}-->Lambda V, where V is a vector meson (1^-), has been done by putting together kinematical and dynamical analysis. An intensive use of the helicity formalism is involved on the kinematical side,…

High Energy Physics - Phenomenology · Physics 2011-06-07 Aqeel Ahmed

We calculate the branching ratios of the hadronic \Lambda_b decays to \eta and \eta^\prime in the factorization approximation where the form factors are estimated via QCD sum rules and the pole model. Our results indicate that, contrary to…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. R. Ahmady , C. S. Kim , Sechul Oh , Chaehyun Yu

Semileptonic and nonleptonic decays of the B_c meson to B_s and B mesons, caused by the c\to s,d quark transitions, are studied in the framework of the relativistic quark model. The heavy quark expansion in inverse powers of the active c…

High Energy Physics - Phenomenology · Physics 2011-03-23 D. Ebert , R. N. Faustov , V. O. Galkin

A relativistic quark model is applied to the description of semileptonic and non-leptonic charmed decays of the B-meson. The exclusive semileptonic modes B -> D l \nu and B -> D* l \nu are described through the universal Isgur-Wise form…

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

Employing the QCD factorization formalism we compute $B_{u}^{-} \to \gamma^{\ast} \, \ell \, \bar \nu_{\ell}$ form factors with an off-shell photon state possessing the virtuality of order $m_b \, \Lambda_{\rm QCD}$ and $m_b^2$,…

High Energy Physics - Phenomenology · Physics 2022-03-09 Chao Wang , Yu-Ming Wang , Yan-Bing Wei

In light of the LHCb observations about the $B_s \to D_s^{(*)}\ell \nu_\ell$ semileptonic decays, we study these channels within the Standard Model framework of covariant confined quark model. The necessary transition form factors are…

High Energy Physics - Phenomenology · Physics 2023-02-21 Nakul R. Soni , Aidos Issadykov , Akshay N. Gadaria , Zhomart Tyulemissov , Janaki J. Patel , Jignesh N. Pandya

Based on the helicity method, formulae for the semileptonic transition of $\Lambda_b^0 \to \Lambda_c^+ \ell^- \bar \nu_\ell$ including lepton mass effects are derived. In order to calculate the form factors of the $\Lambda_b$ baryon…

High Energy Physics - Phenomenology · Physics 2025-03-14 Sara Rahmani

We examine the semileptonic $B \to D^{(*)} \ell \nu_\ell$ and $B \to \pi \ell \nu_\ell$ decays adopting the unitarity-based Dispersive Matrix (DM) method, which allows to determine the shape of the relevant hadronic form factors (FFs) in…

High Energy Physics - Phenomenology · Physics 2022-03-31 G. Martinelli , M. Naviglio , S. Simula , L. Vittorio

We reanalyze the $\Lambda_b\to p$ transition form factors in the perturbative QCD (PQCD) approach by including higher-twist light-cone distribution amplitudes (LCDAs) of a $\Lambda_b$ baryon and a proton. The previous PQCD evaluation…

High Energy Physics - Phenomenology · Physics 2022-08-24 Jia-Jie Han , Ya Li , Hsiang-nan Li , Yue-Long Shen , Zhen-Jun Xiao , Fu-Sheng Yu

The form factors parameterizing the B_c semileptonic matrix elements can be related to a few invariant functions if the decoupling of the spin of the heavy quarks in B_c and in the mesons produced in the semileptonic decays is exploited. We…

High Energy Physics - Phenomenology · Physics 2011-03-23 P. Colangelo , F. De Fazio

In these lectures I first cover radiative and semileptonic B decays, including the QCD corrections for the quark subprocesses. The exclusive modes and the evaluation of the hadronic matrix elements, i.e. the relevant hadronic form factors,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Josip Trampetic

We provide upper and lower bounds on the semileptonic weak decay form factors for $B \to D^(*)$ and $\Lambda_b \to \Lambda_c$ decays by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to second order…

High Energy Physics - Phenomenology · Physics 2009-10-31 Cheng-Wei Chiang

An explicit relativistic light-front quark model is presented which gives the momentum transfer dependent form factors of weak hadronic currents among heavy pseudoscalar and vector mesons in the whole accessible kinematic region $ 0\leq q^2…

High Energy Physics - Phenomenology · Physics 2008-02-03 N. B. Demchuk , P. Yu. Kulikov , I. M. Narodetskii , Patrick J. O'Donnell

Weak transition form factors among heavy pseudoscalar mesons are investigated within a relativistic quark model formulated on the light-front. It is shown that the light-front result derived in the time-like region for the matrix elements…

High Energy Physics - Phenomenology · Physics 2008-02-03 N. B. Demchuk , I. L. Grach , I. M. Narodetski , S. Simula

We propose a method of extracting the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ from two-body hadronic decay processes of $B\to DK$ with precisely determined form factors of $B$ meson semi-leptonic decays. The amplitude…

High Energy Physics - Phenomenology · Physics 2019-12-06 Noriaki Kitazawa , Kyo-suke Masukawa , Yuki Sakai