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Related papers: Forward-backward asymmetries in $\Lambda_b \righta…

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Within the Standard Model, we investigate the weak decays of $\Lambda_b \to \Lambda + \gamma$ and $\Lambda_b \to \Lambda + l^{+} l^{-}$ with the light-cone sum rules approach. The higher twist distribution amplitudes of $\Lambda$ baryon to…

High Energy Physics - Phenomenology · Physics 2014-11-18 Yu-ming Wang , Ying Li , Cai-Dian Lu

We discuss two dedicated observables in exclusive B -> K* l+ l- decay that can be used to study effects of physics beyond the standard model, namely the forward-backward asymmetry in the lepton spectrum and the isospin-asymmetry between…

High Energy Physics - Phenomenology · Physics 2014-11-17 Thorsten Feldmann , Joaquim Matias

The exclusive semileptonic decay Lambda_b -> Lambda_c + l nu_l is investigated including both radiative and first-order power corrections in the inverse heavy-quark mass, while the Isgur-Wise function is calculated within a light-front…

High Energy Physics - Phenomenology · Physics 2009-10-31 F. Cardarelli , S. Simula

Leptonic and semi-leptonic rare decays of B-mesons are very clean (both theoretically and experimentally) signatures of any new physics beyond the Standard Model (SM). More specifically the decay \btokll has been theoretically observed to…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. R. Choudhury , A. S. Cornell , Naveen Gaur , G. C. Joshi

The relatively clean theoretical probes of the Standard Model (SM), and the various theories beyond the SM, provided by radiative, semi-leptonic and (purely) leptonic decays of B-mesons have become increasingly important. Due to the large…

High Energy Physics - Phenomenology · Physics 2011-03-23 A. S. Cornell , Naveen Gaur

We investigate the rare baryonic exclusive decays of $\Lambda_b\to \Lambda l^+ l^- (l=e,\mu,\tau)$ with polarized $\Lambda $. Under the approximation of the heavy quark effective theory (HQET), in the standard model we derive the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Chuan-Hung Chen , C. Q. Geng

We study B->K(*)l+l- decays (l=e,mu) based on a data sample of 657 million BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K* polarization, and the…

High Energy Physics - Experiment · Physics 2009-10-29 J. -T. Wei , P. Chang

In 2015, the LHCb collaboration has measured $\frac{d{\mathcal{B}}}{dq^2}$, the lepton- and hadron-side forward-backward asymmetries, denoted by $A^\ell_{FB}$ and $A^{\Lambda}_{FB}$, respectively in the range $15 < q^2(=s) < 20$ GeV$^2$…

High Energy Physics - Phenomenology · Physics 2019-12-06 Aqsa Nasrullah , M. Jamil Aslam , Saba Shafaq

We use the light front quark model to investigate the form factors in the $e^{+}e^{-} \to B\bar{B}$ collision proceses with $B=\Lambda,~\Sigma$ and $\Xi$. These form factor behaviors are calculated based on the Bethe-Salpeter formalism with…

High Energy Physics - Phenomenology · Physics 2026-05-14 Chong-Chung Lih , Chao-Qiang Geng

Form factors of the rare $\Lambda_{b}(\Lambda_{b}^*)\to N\ell^{+}\ell^{-}$ decays are calculated in the framework of the light cone QCD sum rules by taking into account of the contributions from the negative parity baryons. Using the…

High Energy Physics - Phenomenology · Physics 2018-08-29 T. M. Aliev , T. Barakat , M. Savci

We study the semileptonic decays of $\Lambda_c^+ \to \Lambda(n)\ell^+ \nu_{\ell}$ in two relativistic dynamical approaches of the light-front constituent quark model (LFCQM) and MIT bag model (MBM). By considering the Fermi statistic…

High Energy Physics - Phenomenology · Physics 2020-05-20 C. Q. Geng , Chong-Chung Lih , Chia-Wei Liu , Tien-Hsueh Tsai

In this paper, we compute the forward-backward asymmetry and the isospin asymmetry of the $B \to K^* \mu^+ \mu^-$ decay. The $B \to K^*$ transition form factors (TFFs) are key components of the decay. To achieve a more accurate QCD…

High Energy Physics - Phenomenology · Physics 2018-03-28 Hai-Bing Fu , Xing-Gang Wu , Wei Cheng , Tao Zhong , Zhan Sun

We reconstruct the rare decays $B^+ \to K^+\mu^+\mu^-$, $B^0 \to K^{*}(892)^0\mu^+\mu^-$, and $B^0_s \to \phi(1020)\mu^+\mu^-$ in a data sample corresponding to $4.4 {\rm fb^{-1}}$ collected in $p\bar{p}$ collisions at $\sqrt{s}=1.96 {\rm…

High Energy Physics - Experiment · Physics 2015-03-17 CDF Collaboration , T. Aaltonen

Using improved theoretical calculations of the decay form factors in the Light Cone-QCD sum rule approach, we investigate the decay rates, dilepton invariant mass spectra and the forward-backward (FB) asymmetry in the decays $B \to (K,K^*)…

High Energy Physics - Phenomenology · Physics 2011-03-23 A. Ali , Patricia Ball , L. T. Handoko , G. Hiller

A measurement of the forward--backward asymmetry of $e^{+}e^{-} \to c\bar{c}$ and $e^{+}e^{-} \to b\bar{b}$ on the $Z$ resonance is performed using about 3.5 million hadronic $Z$ decays collected by the DELPHI detector at LEP in the years…

High Energy Physics - Experiment · Physics 2010-04-08 DELPHI Collaboration , P. Abreu et al

We study the doubly-polarized lepton pair forward-backward asymmetries in (Lambda_b -> Lambda l^+ l^-) decay using a general, model independent form of the effective Hamiltonian. We present the general expression for nine…

High Energy Physics - Phenomenology · Physics 2009-11-10 T. M. Aliev , V. Bashiry , M. Savci

We study B->K(*)l+l- decays based on a large data sample of 657 million BB pairs collected with the Belle detector at the KEKB e+e- collider. The differential branching fraction, the isospin asymmetry, the K* polarization, and the…

High Energy Physics - Experiment · Physics 2008-10-03 The Belle Collaboration , I. Adachi

We present the first lattice QCD determination of the $\Lambda_b \to \Lambda$ transition form factors that govern the rare baryonic decays $\Lambda_b \to \Lambda l^+ l^-$ at leading order in heavy-quark effective theory. Our calculations…

High Energy Physics - Lattice · Physics 2013-04-08 William Detmold , C. -J. David Lin , Stefan Meinel , Matthew Wingate

We present an investigation of the Isgur-Wise form factor relevant for the semileptonic decay Lambda_b -> \Lambda_c + l nu_l performed within a light-front constituent quark model. Adopting different baryon wave functions it is found that…

High Energy Physics - Phenomenology · Physics 2009-10-31 F. Cardarelli , S. Simula

The transition form factors of $B_{(s)} \to S$, with $S$ denoting a scalar meson, are investigated in the light-cone sum rules approach. The numerical values are approximately twice as large as that estimated in the light-front quark model…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yu-Ming Wang , M. Jamil Aslam , Cai-Dian Lu