Related papers: Exotic vector charmonium and its leptonic decay wi…
We report the recent evidence for a new narrow structure, Y(4140), decaying to the $J/\psi \phi$ final state, in exclusive $B^+\to J/\psi\phi K^+$ decays in a data sample corresponding to an integrated luminosity of 2.7 \ifb collected at…
Using the QCD sum rule approach we study the Y(4260) state assuming that it can be described by a mixed charmonium-tetraquark current with $J^{PC}=1^{--}$ quantum numbers. For the mixing angle around $\theta \approx (53.0\pm 0.5)^{0}$, we…
We use QCD sum-rules to predict ground state masses for pseudoscalar ($J^{PC}=0^{-+}$) charmonium and bottomonium hybrids. We find that the inclusion of a six-dimensional gluon condensate contribution is needed to stabilize the analyses.…
Exotic charmonium and bottonomium resonances recently discovered are discussed and interpreted as diquark-antidiquark states containing a pair of charm quarks and a pair of light, up and down, quarks. Successes, shortcomings and predictions…
In this work, we study the charmonium spectrum within an unquenched quark model including coupled-channel effects. In couple-channel calculations, we include all of the opened charmed meson channels with the once-subtracted method,…
The masses of the ground state and excited heavy tetraquarks with hidden charm and bottom are calculated within the relativistic diquark-antidiquark picture. The dynamics of the light quark in a heavy-light diquark is treated completely…
In the quark model, hadrons are dominantly bound states of quark-antiquark pairs (mesons) or three quarks (baryons), but QCD also allows hadronic states to be composed of more quarks bound together. Recently, BESIII, Belle and LHCb have…
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…
Charmonium, the spectroscopy of c\bar{c} mesons, has recently enjoyed a renaissance with the discovery of several missing states and a number of unexpected charmonium-like resonances. The discovery of these new states has been made possible…
By extracting the transition amplitudes, we give the first lattice QCD prediction of the two-body decay partial widths of the $1^{-+}$ charmoniumlike hybrid $\eta_{c1}$. Given the calculated mass value $m_{\eta_{c1}}=4.329(36)$ GeV, the…
Using the operator product expansion and nonrelativistic QCD we study the production of charmonium hybrids in B decays. We express the decay rate in terms of a few matrix elements which eventually will be fixed by experimental measurements…
The strangeonium-like $s\bar{s}g$ hybrids are investigated from lattice QCD in the quenched approximation. In the Coulomb gauge, spatially extended operators are constructed for $1^{--}$ and $(0,1,2)^{-+}$ states with the color octet…
In this article, we study the vector meson transitions among the charmonium and bottomonium states with the heavy quark effective theory in an systematic way, and make predictions for the ratios among the vector meson decay widths of a…
This contribution briefly discusses some new theoretical results for the properties of charmonium, especially the "higher charmonium" states above open-charm threshold. In particular we discuss the spectrum of states, open-flavor strong…
Model-independent features of hybrid states with heavy quarks and adiabatic approximation for such systems are discussed.These general arguments are applied to the QCD-based constituent gluon model.The leading- order Hamiltonian is derived…
We investigate the heavy quarkonium hybrid mesons with exotic quantum numbers $J^{PC}=2^{+-}$ via QCD sum rule method. We construct the currents with three Lorentz indices and calculate the correlation functions up to dimension six at the…
The discovery of hadronic states beyond the conventional two-quark meson and three-quark baryon picture in the last two decades is one of the most amazing accomplishments in fundamental physics research. We review the experimental progress…
Strong decays of the charmonium-like state $Y(4320)$ have been studied in the framework of the covariant confined quark model. The resonance $Y$ has been interpreted as a four-quark state of the molecular type. We evaluate the hidden-charm…
We review how quark models are able to describe the phenomenology of the charm meson sector. The spectroscopy and decays of charmonium and open charm mesons are described in a particular quark model and compared with the data and the…
We investigate the spectroscopy and decays of the charmonium and upsilon systems in a potential model consisting of a relativistic kinetic energy term, a linear confining term including its scalar and vector relativistic corrections and the…