Related papers: Pseudoscalar mixing in J/psi and psi(2S) decay
A pseudoscalar associated with dynamical symmetry breaking can mix with a heavier scalar when CP is violated. We study how such a mixed state that is mostly pseudoscalar can resemble the observed 125 GeV particle. The production rate from…
We start by presenting the current status of a complex flavour conserving two-Higgs doublet model. We will focus on some very interesting scenarios where unexpectedly the light Higgs couplings to leptons and to b-quarks can have a large…
Nowadays the field of searching for a new physics became a very interesting subject in a light meson decays due to a recent results from KTeV collaboration which found the 3.3\sigma\ disagreement between Standard Model theory and their…
We report determination of branching fractions for the decays psi(2S) --> h + J/psi, where h=any, pi+pi-, pi0pi0, eta, pi0, and gamma gamma through chi_{c0,1,2}. These measurements use 27M psi(2S) decays produced in e+e- collision data…
The CMS collaboration has reported a measurement of $\Upsilon$ decays to ditaus using $61.9~{\rm fb}^{-1}$ of scouting data. If interpreted as the decay of $\Upsilon(1S,2S,3S)$, the measured ditau rate is more than ten times that seen in…
The mass spectra and wave functions of both $1S$ and $2S$ state heavy pseudoscalar ($P$) and vector ($V$) mesons are analyzed within the light-front quark model. Important empirical constraints employed in our analysis of the mass spectra…
We measure the mass of the eta meson using psi(2S) --> eta J/psi events acquired with the CLEO-c detector operating at the CESR e+e- collider. Using the four decay modes eta --> gamma gamma, 3pi0, pi+pi-pi0, and pi+pi-gamma, we find…
The eta(1835) is confirmed clearly in new BESIII data for J/Psi -> gamma (eta'-pi-pi); the angular distribution of the photon is consistent with a pseudoscalar. This makes it a candidate for an s-sbar radial excitation of eta' and eta(1440)…
The decays of pseudoscalar bottomonium eta_b into a pair of vector charmonia, J/\psi J/\psi, J/\psi \psi', \psi' \psi' are considered in the light cone formalism. Relativistic and leading logarithmic radiative corrections to the amplitudes…
We aim to explore the production rate of the pseudoscalar glueball in $J/\psi$ radiative decay by lattice QCD in quenched approximation. The calculation is performed on three anisotropic lattices with the spatial lattice spacing ranging…
Using $\gamma \gamma J/\psi, J/\psi \ra e^+ e^-$ and $\mu^+ \mu^-$ events from a sample of $14.0\times 10^6$ $\psip$ decays collected with the BESII detector, the branching fractions for $\psip\ra \pi^0\J$, $\eta\J$, and…
A generalization of the chiral effective lagrangian of order $p^2$ is proposed which involves the $\eta'$-meson, its excitation, and the pseudoscalar (PS) glueball. Model-independent constraints are found for the contributions to the…
By analyzing existing data on pseudoscalar charmonium decays, we obtain the ratio of the branching fractions of $\eta_c(2S)$ and $\eta_c$ decays into ten different final states with light hadrons. For the first time, we test the two…
Radial mixing in the pseudoscalar $\eta-\eta^{\prime}$ systems can be generated from hyperfine interactions and annihilation terms. For the $\eta-\eta^{\prime}$ system we find the effects of radial mixing are appreciable and seriously…
We reanalyze the eta-gamma and eta'-gamma transition form factors within the modified hard scattering approach on the basis of new experimental data from CLEO and L3. Our approach perfectly describes the experimental data over a wide range…
Masses of the eta and eta-prime mesons are estimated in Nf=2+1 lattice QCD with the non-perturbatively O(a) improved Wilson quark action and the Iwasaki RG-improved gluon action, using CP-PACS/JLQCD configurations on a 16^3 x 32 lattice at…
The $J/{\psi}$ weak decays are rare but possible within the standard model of elementary particles. Inspired by the potential prospects at the future intensity frontier, the $C$ parity violating $J/{\psi}$ ${\to}$…
The results of mixing angle measurement for $\eta'$, $\eta$ mesons generated in charge exchange reactions with $\pi^{-}$ and $K^{-}$ beams are preseneted. When the $\eta'$, $\eta$ mesons are described in nonstrange(NS)--strange(S) quark…
We show that the newly measured branching ratios of vector charmonia ($J/\psi$, $\psi^\prime$ and $\psi(3770))$ into $\gamma P$, where $P$ stands for light pseudoscalar mesons $\pi^0$, $\eta$, and $\eta^\prime$, can be well understood in…
The $\eta'$ which is an $SU(3)_F$ singlet state can contain a pure gluon component, gluonium. We examine this possibility by analysing all available experimental data. It is pointed out that the $\eta'$ gluonic component may be as large as…