Related papers: Exclusive Rare Decays of Heavy Baryons to Light Ba…
Hadronic matrix elements of the vector, axial-vector and tensor currents relevant for exclusive rare decays $B\to(\pi,\rho,K,K^*)\,l^+l^-$ induced by the quark transition $b\to d,s$ are analysed using dispersion formulation of the…
We present a detailed theoretical analysis of very rare, exclusive hadronic decays of the electroweak gauge bosons V=W, Z from first principles of QCD. Our main focus is on the radiative decays V->M+gamma, in which M is a pseudoscalar or…
The semileptonic transition of $\Lambda_b$ baryon is studied using the Hypercentral constituent quark model. The six-dimensional hyperradial $Schr\ddot{o}dinger$ equation is solved in the variational approach to get masses and wavefunctions…
Motivated by the observation of the decay $\bar{B}\to \bar{K}^*\gamma$ by CLEO, we have systematically analyzed the two-body weak radiative decays of bottom and charmed hadrons. There exist two types of weak radiative decays: One proceeds…
We construct light-cone sum rules for various types of effective form factors in the $\Lambda_b \to \Lambda \ell^+\ell^-$ and $\Lambda_b \to \Lambda \gamma$ decays by analyzing vacuum-to-$\Lambda_b$ (or $\gamma^\ast$-to-$\Lambda_b$)…
We study the exclusive rare decay B -> K l(bar) l. We calculate the relevant form factors within a relativistic constituent quark model, for the first time without employing the impulse approximation. The calculated form factors are used to…
We present within the Standard Model the exclusive radiative decays B -> K*/rho gamma and B_(s/d) -> gamma gamma in QCD factorization based on the heavy-quark limit m_b >> Lambda_QCD. For the decays with a vector meson in the final state we…
The measurements of rare decays are highly sensitive to physics beyond the standard model. In this article limits on the branching ratios of the decays B0s -> mu+mu-, D0 -> mu+mu- and D+ -> pi+mu+mu- are presented. Furthermore the first…
The nonleptonic decays $\Lambda_{b}\rightarrow\Sigma_{c}^{*-}\pi^{+},\Xi_{c}^{*0}K^{0}$ and $\Lambda_{b}\rightarrow\Delta^{0}D^{0},\Sigma^{*-}D_{0}^{+}$ are studied. In addition, the decays…
The rare exclusive dileptonic $\Lambda_{b}\to \Lambda\ell^{+}\ell^{-}$ $(\ell =\mu, \tau)$ decays are investigated in the general two-Higgs-doublet model of type III. A significant enhancement to the branching ratios, differential branching…
The transition form factors responsible for the radiative $\Sigma_Q \to \Lambda_Q \gamma$ and $\Xi_Q^\prime \to \Xi \gamma$ decays of the negative parity baryons are examined within light cone QCD sum rules. The decay widths of the…
We reconsider the QCD predictions for the radiative decay $B\to \gamma \ell \nu_\ell$ with an energetic photon in the final state by taking into account the $1/E_\gamma, 1/m_b$ power-suppressed hard-collinear and soft corrections from…
We calculate the decay width of the $\Lambda_{c}^{+}\to\Sigma^{+}\gamma$ using light-cone sum rules. For the initial quark radiation an effective Hamiltonian is constructed, where the internal quark line shrinks to a point. The final quark…
Rare and very rare decays of third-generation particles, including $b$-hadrons and $\tau$ leptons, provide sensitive probes of physics beyond the Standard Model (SM). Unlike direct searches limited by collider energies, they probe new…
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…
We discuss some selected topics in rare B decays in the context of the standard model and compare theoretical estimates with available data. Salient features of the perturbative-QCD and power corrections in the decay rate for $B \to X_s +…
The semileptonic weak decay process of the $\Lambda_c$ baryon to the neutron $\Lambda_c\rightarrow ne^+\nu_e$ is examined. The transition form factors are investigated with light-cone QCD sum rules. The differential decay width is obtained…
We investigate rare special dileptonic decays of $ \Lambda_b$, $\Sigma_b$ and $\Xi_b $ baryons in the Standard Model and context of the general Two-Higgs-Doublet Model with Type III. Specifically, we consider the decays $ \Lambda_b…
We study the rare decays $\Lambda_b \rightarrow \Lambda l^+ l^-~(l=e,\mu, \tau)$ in the Bethe-Salpeter equation approach. We find that depending on the values of parameters in our model the branching ratio $Br(\Lambda_b \rightarrow \Lambda…
We give a brief overview of phenomenological developments in the analysis of angular observables for exclusive decay modes of $B$ mesons and $\Lambda_b$ baryons, with focus on recent results and some important aspects related to the…