Related papers: Spin-$1/2$ invisible particles in heavy meson deca…
We present a search for flavor changing neutral currents in decays of top quarks. The analysis is based on a search for ttbar -> l'null + jets (l, l' = e, mu) final states using 4.1 fb^-1 of integrated luminosity of ppbar collisions at…
We present results from BABAR experiment for the measurement of inclusive and exclusive branching fractions of B mesons into final states containing $J/\psi$, $\psi(2S)$ and $\chi_c$. The contributions of CP even and odd amplitudes in the…
The decays of non-strange negative parity baryons via the emission of single $\pi$ and $\eta$ mesons are analyzed in the framework of the $1/N_c$ expansion. A basis of spin-flavor operators for the partial wave amplitudes is established to…
We investigate the possibility of observing the exotic decay mode of the top quark into the lightest stop ($\tilde t_1$) and neutralino ($\tilde\chi^0_1$) in the minimal supersymmetric standard model with R-parity at the upgraded Tevatron.…
Inspired by the recent discovery of the $\Xi_{cc}^{++}$ by the LHCb Collaboration, we study the magnetic moments of the spin-1/2 doubly charmed baryons up to the next-to-leading order in covariant baryon chiral perturbation theory with the…
The four decay modes $D^{0}\to\phi\pi^{0}$, $D^{0}\to\phi\eta$, $D^{+}\to\phi\pi^{+}$, and $D^{+}\to\phi K^{+}$ are studied by using a data sample taken at the centre-of-mass energy $\sqrt{s} = 3.773$~GeV~with the BESIII detector,…
We have performed a search for the flavor-changing neutral-current decays B --> pi l+l-, where l+l- is either e+e- or mu+mu-, using a sample of 230 million Y(4S)-->BBbar decays collected with the BABAR detector. We observe no evidence of a…
The spectroscopic properties of single heavy spin-1/2 $\Lambda_{Q}$, $\Sigma_{Q}$, $\Xi^{(\prime)}_{Q}$ and $ \Omega_{Q}$ baryons are investigated at finite temperature in the framework of thermal QCD sum rule. We discuss the behavior of…
We search for b to s\mu^+\mu^- transitions in B meson (B^+, B^0, or B^0_s) decays with 924pb^{-1} of p pbar collisions at sqrt(s)=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We find excesses with significances of…
Searches for $B$ mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either $\Lambda_c$ or $\Lambda$ and the lepton is a muon or an electron. These decays violate both baryon and lepton number…
An extension of the Standard Model to the local gauge group $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ which is a subgroup of the electroweak-strong unification group $E_6$ is analyzed. The mass scales, the gauge boson masses, and the masses…
More than two decades ago, we studied heavy-flavor-conserving weak decays of heavy baryons within the framework that incorporates both heavy-quark and chiral symmetries. In view of the first observation of $\Xi_b^-\to\Lambda_b^0\pi^-$ by…
The perturbative QCD calculation of heavy quark fragmentation into a heavy meson is extended to predict fragmentation into heavy flavor baryons. This is accomplished by implementing the quark-diquark model of the baryons. Several diquark…
We study the neutrinoless double beta decays of spin-1/2 hyperons, $B_1^- \to B_2^+ \ell^- \ell^-$ with $B_1^-\in \{\Sigma^-,\Xi^-\}$ and $B_2^+\in\{p,\Sigma^+\}$, which violate lepton number by two units. The decay amplitudes are computed…
The flavor-changing neutral current (FCNC) decays of charmed hadrons with missing energy $(\not\!\!E)$ can serve as potentially promising hunting grounds for hints of new physics, as the standard-model backgrounds are very suppressed. A few…
We study two-body $B_{(c)}\to M_c(\pi,K)$ and semileptonic $B_{c}\to M_c\ell^-\bar \nu_\ell$ decays with $M_c=(J/\psi,X_c^0)$, where $X_c^0\equiv X^0(3872)$ is regarded as the tetraquark state of $c\bar cu\bar u(d\bar d)$. With the decay…
Flavor changing neutral current (FCNC) interactions for a top quark $t$ decays into $Xq$ with $X$ represents a neutral gauge or Higgs boson, and $q$ a up- or charm-quark are highly suppressed in the Standard Model (SM) due to the…
$U(1)^\prime$ extensions of the standard model with generation-dependent couplings to quarks and leptons are investigated as an explanation of anomalies in rare $B$-decays, with an emphasis on stability and predictivity up to the Planck…
The basic structure of top-quarks as spin-1/2 particles is characterized by the radius $R_t$ and the intrinsic magnetic dipole moment $\kappa_t$, both individually associated with gauge interactions. They are predicted to be zero in…
We present the first evidence of charmless decays of the $B_s^0$ meson, the decay \phiphi, and a measurement of the Branching Ratio $\BR(\phiphi)$ using $180 {\rm pb}^{-1}$ of data collected by the \cdfii experiment at the Fermilab Tevatron…