One of the most intriguing puzzles in hadron spectroscopy are the numerous charmonium-like states observed in the last decade, including charged states that are manifestly exotic. The $BABAR$ and Belle experiments have extensively studied those in B
meson decays, initial state radiation processes and two photon reactions. We can question what we have understood after 11 year search in this field, and try to combine results to conclude on what these new unpredicted resonant states are, and how they can be accommodated in the theory. Big effort has been made from theoretical and experimental point of view, as the potential models unlikely explain the presence of so many enhancements, for mass values above the $D bar D$ threshold. In this report the $BABAR$ and Belle results of the two invariant mass systems of $J/psi phi$ and $J/psi omega$ are put in comparison in a search for non-conventional charmonium states. This involves the study of the systems of $J/psi K^+ K^-$ and $J/psi pi^+ pi^- pi^0$, respectively. There are strong theoretical arguments in favor of the presence of hybrids or exotic states, in those invariant mass distributions. Remarks on these data analyses are given, based on the $BABAR$ and Belle experimental results.
One of the most intriguing puzzles in hadron spectroscopy are the numerous charmonium-like states observed in the last decade, including charged states that are manifestly exotic. The $BABAR$ experiment has extensively studied those in B meson decays
, initial state radiation processes and two photon reactions. The study of the process $B rightarrow J/psi phi K$, with a search for the resonant states X(4140) and X(4270) in their decays to $J/psi phi$, will be highlighted. The recent results of the Dalitz analysis of $eta_c$ to 3 pseudoscalar mesons, via 2-photon interactions, will be presented in this report
The $bar PANDA$ experiment at FAIR (Facility for Antiproton and Ion Research) in Darmstadt (Germany) is designed for $bar p p$ annihilation studies and it will investigate fundamental questions of hadron and nuclear physics in interactions of antipro
tons with nucleons and nuclei. Gluonic excitations and the physics of hadrons with strange and charm quarks will be accessible with unprecedented accuracy, thereby allowing high precision tests of the strong interactions. In particular, the $D_{s0}^*(2317)^+$ and $D_{s1}(2460)^+$ are still of high interest 11 years after their discovery, because they can not be simply understood in term of potential models. The available statistics and resolution of the past experiments did not allow to clarify their nature. Recently LHCb at CERN has made progresses in this respect, but still not at the level of precision required in order to clarify the puzzle of the $cs$-spectrum. $bar PANDA$ will be able to achieve a factor 20 higher mass resolution than attained at the B-factories, which is expected to be decisive on these and second-order open questions. The technique to evaluate the width from the excitation function of the cross section of the $D_s$ mesons will be presented, and ongoing simulations performed with $PandaRoot$ will be shown.
One of the most intriguing puzzles in hadron spectroscopy are the numerous charmonium-like states observed in the last decade, including charged states that are manifestly exotic. Over the years, the experiment $BABAR$ has extensively studied those i
n B meson decays, initial state radiation processes and two photon reactions. We report in this paper a new study on some of those states, performed using the entire data sample collected by $BABAR$ in $e^+e^-$ collisions, at center of mass energies near 10.58 GeV/c$^2$. The study of the process $B rightarrow J/psi phi K$ will be presented, and the search for the resonant states X(4140) and X(4270) in their decays to $J/psi phi$, will be highlighted.
The Facility for Antiproton and Ion Research (FAIR) is an international accelerator facility which will use antiprotons and ions to perform research in the fields of nuclear, hadron and particle physics, atomic and anti-matter physics, high density p
lasma physics and applications in condensed matter physics, biology and the bio-medical sciences. It is located at Darmstadt (Germany) and it is under construction. Among all projects in development at FAIR in this moment, this report focuses on the $bar PANDA$ experiment (antiProton ANnihilation at DArmstadt). Some topics from the Charm and Charmonium physics program of the $bar PANDA$ experiment will be highlighted, where $bar PANDA$ is expected to provide first measurements and original contributions, such as the measurement of the width of very narrow states and the measurements of high spin particles, nowaday undetected. The technique to measure the width of these very narrow states will be presented, and a general overview of the machine is provided.
