arXiv subjects

Bo-Chao Liu

Publications and source records attributed to Bo-Chao Liu.

22 records · Page 2Linked to original sources

arXiv2012

Mechanism of $K^- p \to ηΛ$ reaction near threshold

Within an effective Lagrangian approach, we investigate the reaction mechanism of $K^- p\to ηΛ$ near threshold. It is found that a new $D_{03}$ resonance, with mass $M=1668.5\pm 0.5$MeV and width $Γ=1.5\pm0.5$MeV, is needed to interpret the experimental data reported by the Crystal Ball collaboration. To verify our results, remeasurements on the differential cross sections and $Λ$ polarization in this reaction will be helpful. Furthermore, we also show that the reaction $p\bar p\to Λ\bar Λη$ is a good place to look for this new resonance if it exists.

hep-ph↗

arXiv2012

Evidence for a narrow $D_{03}$ state in $K^- p \rightarrow ηΛ$ near threshold

Recently, we reported a theoretical study on the $K^- p \to ηΛ$ 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 $Γ=1.5\pm 0.5$ MeV, which is not the conventional $Λ$(1690) or other $Λ$ state listed in the Particle Data Group book. In the present work, we study the $Λ$ polarization in the $K^- p \to ηΛ$ reaction within the same framework. The results show that the existence of this narrow $D_{03}$ state is also compatible with current $Λ$ polarization data and that the more accurate $Λ$ polarization data at $P_{K^-}=735$MeV can offer further evidence for the existence of this resonance. Furthermore, the role of the $Λ(1690)$ resonance in this reaction is also discussed.

hep-ph↗

arXiv2012

The $K^- p \rightarrow ηΛ$ reaction in an effective Lagrangian model

We report on a theoretical study of the $K^- p \to ηΛ$ reaction near threshold by using an effective Lagrangian approach. The role of $s-$channel $Λ(1670)$, $t-$channel $K^*$ and $u-$channel proton pole diagrams are considered. We show that the total cross sections data are well reproduced. However, only including the $s-$wave $Λ(1670)$ state and the background contribution from $t-$ and $u-$channel are not enough to describe the bowl structures in the angular distribution of $K^- p \to ηΛ$ reaction, which indicates that there should be higher partial waves contributing to this reaction in some energy region. Indeed, if we considered the contributions from a $D_{03}$ resonance, we can describe the bowl structures, however, a rather small width ($\sim 2$ MeV) of this resonance is needed.

nucl-th↗

arXiv2012

Resonance model study on $K^+ N \rightarrow K N η$ near threshold

By using resonance model, we investigate $K^+ N \rightarrow K N η$ reactions with the assumption that these reactions are dominated by the excitation of $N^*(1535)$ near threshold. It is found that the hyperon and $ρ$ 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 $KΛ$, $KΣ$ and $Nρ$ 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.

nucl-th↗