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Related papers: Forward-backward asymmetries in (Lambda_b -> Lambd…

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Using the most general model independent form of the effective Hamiltonian, the rare B_s --> \gamma \ell^+ \ell^- decays are studied by taking into account the polarization of the photon. The total and the differential branching ratios for…

High Energy Physics - Phenomenology · Physics 2011-09-13 U. O. Yilmaz , B. B. Sirvanli , G. Turan

After a brief review of the inclusive and exclusive rare semileptonic decays of B mesons in the standard model (SM), an overview of recent theoretical developments in this field is given. New physics effects on various observables such as…

High Energy Physics - Phenomenology · Physics 2009-10-31 Chao-Shang Huang

Using a known result by Falk et al. for the 1/m_b^2 correction to the dilepton invariant mass spectrum in the decay B \rightarrow X_s \mu^+ \mu^-, we calculate the 1/m_b^2 correction to the left-right muon polarization asymmetry in this…

High Energy Physics - Phenomenology · Physics 2011-01-27 Oliver Baer , Nicolas Pott

We study the implication of R-parity violating Rp Minimal Supersymmetric Standard Model (MSSM) model in lepton polarization asymmetry ALP in B l l(bar) decays . The analysis show that the ALP is significant in a certain phenomenological…

High Energy Physics - Phenomenology · Physics 2010-11-23 Azeem Mir , Farida Tahir , Kamaluddin Ahmed

We examine the leptonic forward-backward and polarization (left-right) asymmetries in the dileptonic B -> X_s l^+ l^- decay when the momentum dependence of $\psi$ and $\psi'-\gamma$ conversion strength is taken into account. The results…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mohammad R. Ahmady

We analyze the $B\to K_2^*(\to K\pi)l^+l^-$ (with $l=e,\mu,\tau$) decay in the standard model and two new physics scenarios: vector-like quark model and family non-universal $Z'$ model. We derive its differential angular distributions,…

High Energy Physics - Phenomenology · Physics 2015-03-17 Run-Hui Li , Cai-Dian Lü , Wei Wang

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

Depending on the assumptions on the power corrections to the exclusive b -> s l+ l- decays, the latest data of the LHCb collaboration - based on the 3 fb^-1 data set and on two different experimental analysis methods - still shows some…

High Energy Physics - Phenomenology · Physics 2016-06-29 T. Hurth , F. Mahmoudi , S. Neshatpour

Decay rate, forward-backward asymmetry and polarization asymmetries of final state leptons in B-> K_{1}tau ^{+}tau ^{-}, where K_{1} is the axial vector meson, are calculated in Standard Model and in the universal extra dimension (UED)…

High Energy Physics - Phenomenology · Physics 2008-11-26 Asif Saddique , M. Jamil Aslam , Cai-Dian Lu

We present new calculations of the differential decay rates for $H\to \ell^+\ell^- \gamma$ with $\ell=e$ or $\mu$ in the Standard Model. The branching fractions and forward-backward asymmetries, defined in terms of the flight direction of…

High Energy Physics - Phenomenology · Physics 2020-12-02 Aliaksei Kachanovich , Ulrich Nierste , Ivan Nišandžić

The fact that the measured B to \pi \pi, \pi K branching ratios exhibit puzzling patterns has received a lot of attention in the literature and motivated the formulation of a series of new physics scenarios with enhanced Z-penguins. In this…

High Energy Physics - Phenomenology · Physics 2009-11-11 Gursevil Turan

We study the exclusive flavor chancing neutral current process Lambda(b)-->Lambda neutrino antineutrino in the leptophobic Z-prime model, where charged leptons do not couple to the extra Z-prime boson. The branching ratio, as well as, the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Berin Belma Sirvanli

We obtain analytic expressions for the energy and polar-angle double differential distributions of a secondary lepton l+ (l-) arising from the decay of t (tbar) in e+e- -> t tbar with an anomalous tbW decay vertex. We also obtain analytic…

High Energy Physics - Phenomenology · Physics 2009-10-31 Saurabh D. Rindani

We critically analyze the body of results that hints to the existence of New Physics from possible violations of lepton universality observed by the LHCb experiment in the $\mu/e$ ratios $R_{K}$ and $R_{K^*}$ to the $g-2$ lepton anomalies.…

Using the Bethe-Salpeter equation (BSE) we investigate the forward-backward asymmetries $( A_{FB}) $ in $\Lambda_b \rightarrow \Lambda l^+ l^-(l=e,\mu,\tau)$ in the quark-diquark model. This approach provides precise form factors that are…

High Energy Physics - Phenomenology · Physics 2022-08-29 Liang-Liang Liu , Su-Jun Cui , Jing Xu , Xin-Heng Guo

In this talk I discuss CP violation in hyperon decays in Left-Right symmetric models. I show that the asymmetry in polarization in $\Lambda \to p\pi^-$ can be as large as $6\times 10^{-4}$ in these models, which is an order of magnitude…

High Energy Physics - Phenomenology · Physics 2016-09-01 Xiao-Gang He

In this paper we study the polarization asymmetries of the final state lepton in the radiative dileptonic decay of B meson (\bsllg) in the framework of Minimal Supersymmetric Standard Model (MSSM) and various other unified models within the…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Rai Choudhury , Naveen Gaur

The effective Hamiltonian for the decay $b\to s l^+ l^-$ predicts a characteristic polarization for the final state lepton, which can serve as an important test of the underlying theory. The lepton polarization has, in addition to a…

High Energy Physics - Phenomenology · Physics 2009-10-28 F. Krüger , L. M. Sehgal

We calculate the zeroes of angular observables $P_4^{'}$ and $P_5^{'}$ of 4 - body angular distribution of $B\rightarrow K^{*} (\rightarrow K \pi) l^+ l^-$ where LHCb, in its analysis of form factor independent angular observables, has…

High Energy Physics - Phenomenology · Physics 2016-04-06 Girish Kumar , Namit Mahajan

The current world averages of the ratios $R_{D^{(*)}}$ are about $4\sigma$ away from their Standard Model prediction. These measurements indicate towards the violation of lepton flavor universality in $b\rightarrow c\,l\,\bar{\nu}$ decay.…

High Energy Physics - Phenomenology · Physics 2020-02-18 Suman Kumbhakar , Ashutosh Kumar Alok , Dinesh Kumar , S Uma Sankar