Tests are discussed to distinguish cc̄, hybrid charmonium and molecular interpretations of the narrow Belle resonance at 3872 MeV

In this paper we survey all radial and orbital excitations of the $I$=0 and $I$=1 $n\mathrm{n̄}$ system anticipated up to 2.1 GeV. We give detailed predictions of their quasi-two-body branching fractions and identify characteristic decay modes that can isolate quarkonia; this should be useful in distinguishing quarkonia from glueballs and hybrids. Several of the “missing mesons” with $L_{q\mathrm{q¯}}=2\mathrm{}$ and $L_{q\mathrm{q¯}}=3\mathrm{}$ are predicted to decay dominantly into certain $S+P$ and $S+D$ modes, and should appear in experimental searches for hybrids in the same mass region. We also consider the topical issues of whether some of the recently discovered or controversial meson resonances, including glueball and hybrid candidates, can be accommodated as quarkonia.

We confront predictions for hybrid charmonium and other gluonic excitations in the charm region with recently observed structures in the mass range above 3 GeV. The Y(4260), if resonant, is found to agree with expectations for hybrid charmonium. The possibility that other gluonic excitations may be influencing the data in this region is discussed

In this paper we evaluate strong decay amplitudes and partial widths of strange mesons (strangeonia and kaonia) in the ${}^3{P}_0$ decay model. We give numerical results for all energetically allowed open-flavor two-body decay modes of all $n\overline{s}$ and $s\overline{s}$ strange mesons in the $1S,$ $2S,$ $3S,$ $1P,$ $2P,$ $1D$ and $1F$ multiplets, comprising strong decays of a total of 43 resonances into 525 two-body modes, with 891 numerically evaluated amplitudes. This set of resonances includes all strange $q\overline{q}$ states with allowed strong decays expected in the quark model up to ca. 2.2 GeV. We use standard nonrelativistic simple harmonic oscillator quark model wave functions to evaluate these amplitudes, and quote numerical results for all amplitudes present in each decay mode. We also discuss the status of the associated experimental candidates, and note which states and decay modes would be especially interesting for future experimental study at hadronic, $e^{+}{e}^{-}$ and photoproduction facilities. These results should also be useful in distinguishing conventional quark model mesons from exotica such as glueballs and hybrids through their strong decays.