Related papers: Gluonic Excitations in Mesons
The eta(1760) may be significantly produced in J/Psi radiative decay. We deduce from experimental data that its branching ratio to two gluons is bounded, 0.4 +- 0.3 < BR(eta(1760) -> gg) < 0.9 +- 0.3, consistent with gluonic admixture.…
We analyze the process $\vec \gamma +p\to \rho^0 \pi^{+}n$ at low momentum transfer focusing on a possibility of production of an exotic $J^{PC}=1^{-+}$ meson state. In particular we discuss polarization observables and conclude that linear…
The experimental information on the search for non $q \bar q$ mesons as glueballs, hybrids and multiquark states is reviewed. Candidate states which are particularly amenable to detailed study by accumulating large samples of $J/\psi$,…
One of the unanswered and most fundamental questions in physics regards the nature of the confinement mechanism of quarks and gluons in QCD. Exotic hybrid mesons manifest gluonic degrees of freedom and their spectroscopy will provide the…
Exotic mesons with quantum numbers of a hybrid ($\bar{q} q g$) such as $J^{PC} = 1^{-+}$are shown to exist as narrow resonant states in the large $N_c$ limit of QCD. The width of these states is proportional to $1/N_c$. Possible…
The double-gluon hybrid meson configuration was recently proposed and investigated within QCD sum rules. In this talk, we discuss the color structures of the double-gluon hybrid meson and construct current operators with exotic quantum…
The ground and first excited states of the hybrid charmonium ${\bar c} c g$, with non-exotic quantum numbers $J^{PC}=0^{-+}$, $1^{--}$ and $1^{++}$ are investigated using quenched lattice QCD. They are completely ignored in the literature,…
The $\eta \pi^{-}$ system has been studied in the reaction $\pi^{-} p \to \eta \pi^{-} p$ at 18 GeV/c. A large asymmetry in the angular distribution is observed indicating interference between L-even and L-odd partial waves. The…
We discuss a coupled channel analysis of the $\eta\pi$ and $\eta'\pi$ systems produced in $\pi^-p$ interactions at 18 GeV/$c$. We show that known $Q\bar Q$ resonances, together with residual soft meson-meson rescattering, saturate the…
The discrepancy between theory and data in the momentum distribution of slow J/psi in B decays has been several times addressed as a puzzle. Using the most recent results on exclusive B decays into J/psi and heavy kaons or exotic mesons and…
In this paper we investigate the Exotic Charmonium (EC) production in $\gamma \gamma$ interactions present in proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN Large Hadron Collider (LHC) energies as well as for the…
The light-mass exotics with J^{PC}=1^{-+} observed at BNL and CERN may have a simple explanation as dynamically generated resonances in eta-prime pi rescattering in the final state interaction. This dynamics is mediated by the same…
We reconsider the discrepancy between theory and data in the momentum distribution of slow J/psi in B decays. Beside an update of the standard color singlet and color octet QCD components, we include the contribution from XY Z exotic…
We discuss in general the construction of gauge-invariant non-local meson operators on the lattice. We use such operators to study the $P$- and $D$-wave mesons as well as hybrid mesons in quenched QCD, with quark masses near the strange…
In this short review we present and discuss all the experimental information about the charged exotic charmonium states, which have been observed over the last five years. We try to understand their properties such as masses and decay…
QCD sum-rules are used to calculate the $\hat\rho(1^{-+})\to\pi\eta, \pi\eta'$ decay widths of the exotic hybrid in two different $\eta-\eta'$ mixing schemes. In the conventional flavour octet-singlet mixing scheme, the decay widths are…
Exotic decays of the Standard Model-like Higgs boson into beyond-the-Standard Model particles are predicted in a wide range of well-motivated theories. The enormous samples of Higgs bosons that have been and will be produced at the Large…
Exotic charmonium-like states have been targeted by various experiments in the last 15 years, but their nature still is unknown. Photo-(muo)production is a new promising instrument to study them. COMPASS, a fixed target experiment at CERN,…
One of the unanswered and most fundamental questions in physics regards the nature of the confinement mechanism of quarks and gluons in quantum chromodynamics (QCD). Exotic hybrid mesons manifest gluonic degrees of freedom and their…
A full amplitude analysis of $\Lambda_b^0 \to J/\psi p \pi^-$ decays is performed with a data sample acquired with the LHCb detector from 7 and 8 TeV $pp$ collisions, corresponding to an integrated luminosity of 3 fb$^{-1}$. A significantly…