Related papers: Double-lepton polarization asymmetries in Lambda_b…
We present a systematic analysis for the rare baryonic exclusive decays of $\Lambda_b\to\Lambda l^+ l^- (l=e,\mu,\tau)$. We study the differential decay rates and the di-lepton forward-backward, lepton polarization and various CP…
In recent times, several hints of lepton non-universality have been observed in semileptonic $B$ meson decays, both in the charged-current ($b \to c l \bar \nu_l$) and neutral-current ($b \to s ll $) transitions. Motivated by these…
Rare B decays provides an opportunity to probe for new physics beyond the standard model. the effective Hamiltonian for the decay $b \to s l^+ l^-$ predicts the characteristic polarization for the final state lepton. Lepton polarization…
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…
Using the most general, model independent effective Hamiltonian, the rare B_s ->\gamma \nu \bar{\nu} decay with polarized photon is studied. The sensitivity of the branching ratio and photon polarization to the new Wilson coefficients are…
Motivated by the recent LHCb results of lepton flavour violation on b decays into s and b decays into c transitions we study the lepton flavour violating (LFV) baryonic decays {Lambda}_b decays into {Lambda}l_i^+ l_j^- in non-universal Z^'…
New CP-violating asymmetries of decay leptons in $e^+\,e^-\;\ra\;t\,\bar{t}$, arising from electric and weak dipole couplings of $t\,\bar{t}$ to $\gamma$ and $Z$, are examined in the case of unpolarized and longitudinally polarized…
We study the rare $\Lambda_b\to\Lambda\mu^+\mu^-$ decay in the Standard Model and beyond. Beyond the Standard Model we include new vector and axial-vector operators, scalar and pseudo-scalar operators, and tensor operators in the effective…
Recently several measurements in the neutral current sector $b\rightarrow s l^+l^-$ ($l=e$ or $\mu$) as well as in the charged current sector $b \rightarrow c \tau \bar{\nu}$ show significant deviations from their Standard Model…
The differential branching ratio, forward-backward asymmetry, CP asymmetry and lepton polarization for a B-meson to decay to strange hadronic final states and a $\tau^+\tau^-$ pair in a CP softly broken two Higgs doublet model are computed.…
We analyze the baryonic semilepton decay $\Lambda_{b} \rightarrow$ $\Lambda \mu^{+} \mu^{-}$ in the scalar leptoquark models with $X(3,2,7/6)$ and $X(3,2,1/6)$ states, respectively. We also discuss the effects of this two NP models on some…
The transverse lepton polarization asymmetry in pi_l2gamma decays may probe T-violating interactions beyond the Standard Model. Dalitz plot distributions of the expected effects are presented and compared to the contribution from the…
Inspired by various updated tantalizing results of LHCb on baryonic sector we study the {\Lambda}_b decays into {\Lambda}^* (1520)l^+ l^- decay in non-universal Z^' model. We present the four-fold angular distributions of the decay in terms…
Using the most general effective Hamiltonian comprising scalar,vector and tensor type interactions, we have written the branching ratio, the forward-backward (FB) asymmetry and the normalized FB asymmetry as functions of the new Wilson…
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…
We examine the T-odd transverse lepton and $\Lambda$ polarizations in the baryonic decays of $\Lambda_b\to\Lambda l^+l^- (l=e ,\mu)$ to study the T violating effects. We show that the lepton polarizations are suppressed but the $\Lambda$…
In this paper we analyze the dilepton mass square $q^2$ dependency of single lepton polarization asymmetries and CP violation for $\overline{B}\rightarrow \overline{K}_0^{*}(1430) \ell^+\ell^-, \ell=\mu,\tau)$ in the 2HDM context. Also, we…
In a recent paper, 8 semileptonic parameters were defined to specify the most general Lorentz-invariant spin correlation functions for 2-body tau decays. These parameters can be used to search for anomalous longitudinal-versus transverse…
We study the lepton forward-backward asymmetry AFB and the longitudinal K* polarization FL, as well as an observable P2 derived from them, in the rare decays B->K*l+l-, where l+l- is either e+e- or mu+mu-, using the full sample of 471…
New BABAR measurements are presented for the exclusive rare decays B -> K(*) l+ l- including branching fractions, isospin asymmetries, direct CP violation, and lepton flavor universality for dilepton masses below and above the J/psi…