123670989
Recent BES results on hadron spectroscopy
Light hadron spectroscopy is a powerful tool in hadronic physics. Several recent BES results on hadron spectroscopy are reported in this proceeding, including the confirmation of the enhancement in p invariant mass in radiative J/Ψ decays, the observation of a charged κ± decaying to K±π0 and the measurement of exclusive decays of the χc0 and χc2 to π0π0 and ηη.
123670989
Recent BES results on hadron spectroscopy
Light hadron spectroscopy is a powerful tool in hadronic physics. Several recent BES results on hadron spectroscopy are reported in this proceeding, including the confirmation of the enhancement in p invariant mass in radiative J/Ψ decays, the observation of a charged κ± decaying to K±π0 and the measurement of exclusive decays of the χc0 and χc2 to π0π0 and ηη.
118860372
Evidence for a narrow $D_{03}$ state in $K^- p \rightarrow \eta \Lambda$ near threshold
Recently, we reported a theoretical study on the $K^- p \to \eta \Lambda$ reaction near threshold by using an effective Lagrangian approach. It was found that the description of angular distribution data measured by the Crystal Ball Collaboration needs a $D_{03}$ resonance with mass $M=1668.5\pm 0.5$ MeV and total decay width $\Gamma=1.5\pm 0.5$ MeV, which is not the conventional $\Lambda$(1690) or other $\Lambda$ state listed in the Particle Data Group book. In the present work, we study the $\Lambda$ polarization in the $K^- p \to \eta \Lambda$ reaction within the same framework. The results show that the existence of this narrow $D_{03}$ state is also compatible with current $\Lambda$ polarization data and that the more accurate $\Lambda$ polarization data at $P_{K^-}=735$MeV can offer further evidence for the existence of this resonance. Furthermore, the role of the $\Lambda(1690)$ resonance in this reaction is also discussed.
118023452
Resonance model study on $K^+ N \rightarrow K N \eta$ near threshold
By using resonance model, we investigate $K^+ N \rightarrow K N \eta$ reactions with the assumption that these reactions are dominated by the excitation of $N^*(1535)$ near threshold. It is found that the hyperon and $\rho$ exchange diagrams give the most important contributions to these reactions. Thus these reactions may be a good place to study the coupling of $N^*(1535)$ with $K\Lambda$, $K\Sigma$ and $N\rho$ channels. We demonstrate that the angular distributions of final particles provide useful information about the different mechanisms of the $N^*(1535)$ excitations, which could be useful for future experimental analysis on these reactions.