Related papers: XYZ States
Charmonium(-like) or bottomonium(-like) states, which are incompatible with predictions from a static quark anti-quark potential model, are often refered to as XYZ states. In this lecture, some peculiar properties of states such as the…
In the past decade, more and more charmoniumlike and bottomoniumlike states have been reported in experiments, which have led us to extensive discussions on the underlying structure of these states. In this review paper, we briefly…
Many charmonium-like and bottomonium-like $XYZ$ resonances have been observed by the Belle, Babar, CLEO and BESIII collaborations in the past decade. They are difficult to fit in the conventional quark model and thus are considered as…
Since 2003 many charmonium-like states were observed experimentally. Especially those charged charmonium-like $Z_c$ states and bottomonium-like $Z_b$ states cannot be accommodated within the naive quark model, which are good candidates of…
In the past decade many charmonium-like states were observed experimentally. Especially those charged charmonium-like $Z_c$ states and bottomonium-like $Z_b$ states can not be accommodated within the naive quark model. These charged $Z_c$…
A review of recent experimental developments concerning the $X$, $Y$ and $Z$ charmonium-like exotic states.
Observations of new charmonium(-like) and bottomonium(-like) states (sometimes refered to as "XYZ" states) at e+e- colliders have changed our picture of quarkonia systems as QCD bound states. Potential models with a linear confinement…
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. Many experiments contributed to this…
Within the past ten years many new hadrons states were observed experimentally, some of which do not fit into the conventional quark model. I will talk about the few-body systems composed of heavy quarks, including the charmonium-like…
In the past decade, due to the experimental observation of many charmonium-like states, there has been a revival of hadron spectroscopy. In particular, the experimental observation of charged charmonium-like, $Z_c$ states, and…
The last few years have witnessed a renaissance in the spectroscopy of heavy quarks. Several long elusive states have now been firmly identified, and several unexpected states have been reported by the high luminosity experiments at Belle,…
Many newly discovered mesons behave like $\ccbar$ charmonium states in that they preferentially decay into final states that contain a $c$- and a $\bar{c}$-quark, but do not fit expectations for any of the unfilled levels of the…
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…
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…
This contribution reviews some recent developments in charmonium spectroscopy, and discusses related theoretical predictions. The spectrum of states, strong decays of states above open charm threshold, electromagnetic transitions, and…
The observation of many unexpected states decaying into heavy quarkonia has challenged the usual Q-Qbar interpretation. We will discuss the nature of some of the charmonium-like resonances recently observed by BES III and LHCb, and their…
A number of charmonium- and bottomonium-like meson states have been observed that have properties that do not match well to expectations for the simple quark-antiquark substructure suggested by the constituent quark model. Some of them are…
Recent experimental results on heavy quarkonia spectroscopy and decays are reviewed. In particular, new results are discussed on charmonium spin singlet states, bottomonium D-states, photon and hadronic transitions from heavy quarkonium…
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…
I review the recent $B$-factory measurements of new states which, in some cases, exhibit Charmonium-like properties, and in other cases suggest the existence of a new spectroscopy. Several theoretical interpretations of the new states have…