Related papers: Rare $\Lambda_{b}\to \Lambda $ l$^{+}$ l$^{-}$ Dec…
Measurements from the LHCb experiment and $B$ factories have revealed several discrepancies in angular observables of rare semileptonic $B$ decays involving the quark-level transition $b \to s \ell^+ \ell^-$. In this work, we conduct a…
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…
In the Standard Model, b quarks produced in e^+e^- annihilation at the Z^0 peak have a large average longitudinal polarization of -0.94. Some fraction of this polarization is expected to be transferred to b-flavored baryons during…
The first observation of the decay $B^{+}\rightarrow p \bar{\it{\Lambda}}$ is presented, using proton-proton collision data collected by the LHCb experiment between 2016 and 2018 at a center-of-mass energy of 13 TeV, corresponding to an…
We examine the new physics sensitivity of the rare decay $\Lambda_b \to \Lambda \nu\bar\nu$ which can be accessible at future $Z$-pole machines like FCC-ee and CEPC. We find that the longitudinal polarization of $\Lambda_b$ baryons produced…
The proton energy spectrum and the angular distribution of the probability of the $\Lambda^+_c$ -> p + $K^-$ + $\pi^+$ decay for the polarized $\Lambda^+_c$ and the unpolarized proton are calculated in the effective quark model with chiral…
We study the polarized $\Lambda_b$ baryon semileptonic decay $\Lambda_b \to \Lambda_cl{\bar\nu}$ using perturbative QCD factorization theorem. In this approach heavy baryon transition form factors are expressed as the convolutions of hard…
Though not considered in general, purely baryonic decays could shed light on the puzzle of the baryon number asymmetry in the universe by means of a better understanding of the baryonic nature of our matter world. As such, they constitute a…
The general analysis of the rare Bc->D^*_s l^+ l^- decay is presented by using the most general, model independent effective Hamiltonian. The dependencies of the branching ratios, longitudinal, normal and transversal polarization…
The relativistic quark model based on the quasipotential approach with the QCD-motivate potential is employed for the calculation of the form factors of the $\Lambda_c\to p$ rare weak transitions. Their momentum dependence is explicitly…
The weak decays of $\Lambda_b \to \Lambda l^{+} l^{-}$ ($l=e, \mu$) are investigated in Minimal Supersymmetric Standard Model (MSSM) and also in Supersymmetric (SUSY) SO(10) Grand Unified Models. In MSSM the special attention is paid to the…
Recently there has been much interest in the tauonic semileptonic meson decays B -> D + tau + nu_tau and B -> D* + tau + nu_tau where one has found larger rates than what is predicted by the Standard Model. We analyze the corresponding…
The rare B decays Bs(d)-->\mu\mu, B-->K*\mu\mu and Bs-->\phi\gamma are studied using up to \sim 0.41 fb^{-1} of pp collisions at \sqrt{s} = 7 TeV collected by the \lhcb experiment in 2010 and 2011. A search for the decays Bs(d)-->\mu\mu, is…
The rare B_s-> \phi \ell^+ \ell^- decay is investigated by using the most general model independent effective Hamiltonian for $\ell= \mu, \tau$. The calculated $Br(B_s \rar \phi \mu^+ \mu^-) = 1.92 \times 10^{-6}$ is in consistent with the…
The New Physics (NP) effects are studied in the rare baryonic decay $\Lambda_b \to \Lambda (\to p\pi^-)\ell^{+}\ell^{-}$, with unpolarized $\Lambda_b$ using most general model independent approach by introducing new axial(vector),…
We study the decays of $\Lambda_b \to \Lambda(\to p \pi^-) \ell ^+ \ell^-$ with $\ell = (e, \mu, \tau)$. In particular, we examine the full angular distributions with polarized $\Lambda_b$ and identify the time-reversal asymmetries or T-odd…
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…
Using the most general, model independent form of effective Hamiltonian, the transverse polarization P_T of Lambda in Lambda_b -> Lambda l^+ l^- decay is studied. It is observed that the averaged <P_T> is very sensitive to the existence of…
Using the light-front quark model, we calculate the transition form factors, decay rates, and longitudinal lepton polarization asymmetries for the exclusive rare $B_s\to (K,\eta^{(\prime)})(\ell^+\ell^-,\nu_{\ell}\bar{\nu_{\ell}}$…
We analyze rare charm baryon decays within the standard model and beyond. We identify all null test observables in unpolarized $\Lambda_c \to p \ell^+ \ell^-$, $\ell=e, \mu$ decays, and study the new physics sensitivities. We find that the…