Related papers: Exotic ccbar spectroscopy
We study the spectroscopy of the states which defy conventional $c\bar{c}$ charmonium and $b\bar{b}$ bottomonium interpretation respectively, and are termed as exotic states. In August 2003 a state X(3872), was discovered [K. Abe\textit{\…
I. Light Scalars as Four-quark States II. Isotensor Tensor Tensor E(1500-1600) State III. X(3872) State as Charmonium \chi_{c1}(2P) IV. Two-gluon Annihilation of Charmonium \chi_{c2}(2P) There are considered problems of the exotic states,…
We present a study of the X(3940) state in the process e+e- -> J/psi D* Dbar. The X(3940) mass and width are measured to be (3942 +7 -6 +- 6)MeV/c^2 and Gamma=(37 + 26 - 15 +- 8 MeV. In the process e+e- -> J/psi D* D*bar we have observed…
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…
We review recent charmonium and charmonium-like state from the BaBar B-factory. A particular focus is given to the observation of the decay $X(3872) \to J/\psi \omega$ and to recent $\eta_{c}(1S)$ and $\eta_{c}(2S)$ results. The Observation…
Current experiments at the B factories, designed to perform precision measurements of matter-antimatter asymmetry in the B meson system, have a much broader physics reach especially in the sector of quarkonium spectroscopy. Here we present…
The charmonium-like exotic states $Y(4230)$ and the less known $Y(4320)$, produced in $e^+e^-$ collisions, are sources of positive parity exotic hadrons in association with photons or pseudoscalar mesons. We analyze the radiative and pion…
We report on exclusive decays of B mesons into final states containing charmonium using data collected with the BABAR detector at the PEP-II storage rings. The charmonium states considered here are J/psi, psi(2S), and chi_C1. Branching…
In this talk, we present the recent study on the charmoniumlike states from the e^+e^- colliders, including BESIII, Belle, BaBar, and CLEOc. The talk covers the X(3872) from the Y(4260) radiative transition, the Y states from the…
I discuss the nature of the new charm and charmonium like states observed in the last few years and measurements that can test these assignments. In particular it appears that the X(3943) is the eta_c''(3^1S_0) which can be tested by…
Recent results on the search for pentaquarks and on charmonium spectroscopy at BaBar are reviewed. The latter includes the observation of the puzzling new state X(3872) -> J/psi pi+ pi- in B decays, and the searches for X(3872) in two-body…
We argue that the resonance-like structures Y(4260) (arXiv:hep-ex/0506081,arXiv:0707.2541), Y(4360), Y(4660) (arXiv:0707.3699) and Y(4635) (arXiv:0807.4458), which were recently reported to have been observed in experiment, are non-resonant…
The possibility of the Y(4260) being the molecular state of $D\bar D_1(2420)+\mathrm{c.c.}$ is investigated in the one boson exchange model. It turns out that the potential of $J^{PC}=1^{--}$ state formed by $D\bar D_1(2420)+\mathrm{c.c.}$…
If the $X(3872)$ is described by the picture as a mixture of the charmonium and molecular $D^{\ast} D$ states; $Y(3940)$ as a mixture of the $\chi_{c0}$ and $D^\ast D^\ast$ states; and $X(4260)$ as a mixture of the tetra-quark and…
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…
The newly observed $X, Y, Z$ exotic states are definitely not in the standard $Q\bar Q'$ structures, thus their existence composes a challenge to our understanding on the fundamental principles of hadron physics. Therefore the studies on…
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…
An interesting controversy has emerged challenging the widely accepted nature of the $X(3915)$ and the $X(3930)$ resonances, which had initially been assigned to the $\chi_{c0}(2P)$ and $\chi_{c2}(2P)$ $c\bar c$ states, respectively. To…
The resonances, containing $c\bar c$ plus $s\bar s$ (or light $q\bar q$) quarks in the mass region $(3900-4700)$ MeV, are analyzed in the relativistic strong coupling theory, with and without channel coupling phenomena. The conventional…
We report preliminary results on the measurement of branching fractions of exclusive decays of neutral and charged B mesons into two-body final states containing a charmonium state and a light strange meson. The charmonium mesons considered…