相关论文: Rare radiative charm decays in the standard model …
We investigate the potential for searching and identifying the leptoquark (LQ) effects in the charm sector through the low-energy polarized scattering processes $\vec{e}^{\,-}p\to e^-\Lambda_c$, $e^-\vec{p}\to e^-\Lambda_c$, and…
We discuss precision tests of the standard model in radiative and semileptonic rare B-decays and CP-violating asymmetries, and possible signatures of supersymmetry in these processes. Motivated by current data, and with an eye on the…
An overview of recent theoretical developments in rare leptonic B decays is given. New physics effects on branching ratio and CP violation in the decays are analyzed in models beyond SM (supersymmetric models and two Higgs doublet models).
The flavor changing transitions in the c->u gamma, c->u gamma gamma and c->u l+ l- offer the possibility to search for new physics in the charm sector. We investigate dominant decay mechanisms in the radiative decays D->V gamma, D->P(V) l+…
I explore the possibility of using heavy meson decays as probes for flavour changing neutral transitions (FCNC) $c\to u\gamma$ and $c\to ul^+l^-$. In the standard model, these are the most frequent FCN transitions among the quarks with…
In this paper, we review recent progress in the field of semileptonic decays of charm mesons, including topics on the relative branching ratio and the form factors. The comparison between the experimental form factor measurements and the…
We review recent experimental progress in the domain of rare radiative, semileptonic and leptonic B decays. The statistical precision attained for these decays has reached a level where they start to impose meaningful constraints on the…
Charmed scalar mesons are studied. By assigning the newly observed charmed strange meson with a narrow width to one of the iso-triplet four-quark mesons, decays of the multiplet members are investigated and, as the consequence, existence of…
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 present a calculation of the rare decay mode D^0 -> gamma gamma, in which the long distance contributions are expected to be dominant. Using the Heavy Quark Chiral Perturbation Theory Lagrangian with a strong g coupling as recently…
The status of heavy-quark decays as of summer 1999 is reviewed. New measurements of semileptonic B decays from LEP and from CLEO are reported and the status of determining the CKM parameters |Vcb| and |Vub| is assessed. Rare charmless…
I report on developments in the experimental and phenomenological understanding of the rare decays of mesons containing b and c quarks, especially as they pertain to the understanding of the CKM matrix and the testing of the standard model.…
We study the rare radiative dileptonic decays $B^0(B_s)\to \gamma\ell^+\ell^-$ ($\ell=e,\mu$) in the standard model. By using the $B$ meson wave function constrained by non-leptonic decays, the branching ratios turn out to be of the order…
The rare Bc->Ds l^+ l^- decay is investigated by using the most general model independent effective Hamiltonian. The general expressions of longitudinal, normal and transversal polarization asymmetries for l^- and l^+ and the combined…
The Standard Model contains a natural source for CP asymmetries in weak decays, which is described by the KM mechanism. Beyond $\epsilon _K$ it generates only elusive manifestations of CP violation in {\em light-}quark systems. On the other…
Using the CLEO II detector at CESR, we observe 500 $\Lambda l^+$ pairs consistent with the semileptonic decay $\Lambda_c \to \Lambda l^+ \nu_{l}$. We measure $\sigma (e^+ e^- \to \Lambda_c X) \dot {cal B}(\Lambda_c^+ \to \Lambda l \nu_{l})…
We determine the radiative decay amplitudes for decay into $D^*$ and $\bar{D} \gamma$, or $D^*_s$ and $\bar{D}_s \gamma$ of some of the charmonium like states classified as X,Y,Z resonances, plus some other hidden charm states which are…
The recently obtained strong evidence for $D^0 - \bar D^0$ oscillations from the $B$ factories provides an important benchmark in our search for New Physics in charm transitions. While the theoretical verdict on the observed values of $x_D$…
We study the rare decays of $B_c^+\to D_{q}^{(*)+}l\bar{l}$ ($q=d,s$ and $l=\nu_l,e,\mu,\tau)$ in the standard model. The form factors are evaluated in the light front and constituent quark models, respectively. We find that the decay…
I provide a comprehensive review of indirect searches for New Physics with charmed mesons. I discuss current theoretical and experimental challenges and successes in understanding decays and mixings of those mesons. I argue that in many New…