Investigating $\Xi$ resonances from pentaquark perspective

Abstract

We have investigated the $qss\bar{q}q$ ($q = u$ or $d$) system to find possible pentaquark explanations for the $\Xi$ resonances. The bound state calculation is carried out within the framework of the quark delocalization color screening model. The scattering processes are also studied to examine the possible resonance states. The current results indicate that the $\Xi(1950)$ can be interpreted as $\Lambda \bar{K}^*$ state with $J^P = 1/2^-$. Three states are identified that match the $\Xi(2250)$, which are $\Sigma^* \bar{K}^*$ state with $J^P = 3/2^-$, $\Sigma^* \bar{K}^*$ state with $J^P =5/2^-$, and $\Xi^* \rho$ state with $J^P =5/2^-$. This may explain the conflicting experimental values for the width of the $\Xi(2250)$. A new $\Xi$ resonance is predicted, whose mass and width are 2066--2079 MeV and 186--189 MeV, respectively. These results contribute to understanding the nature of the $\Xi$ resonances and to the future search for new $\Xi$ resonances. Moreover, it is meaningful to further investigate the $\Xi$ resonances from an unquenched picture on the basis of pentaquark investigation.