QCD sum rule study for hidden-strange pentaquarks*

Abstract

Inspired by the LHCb's observations of hidden-charm $P_{c(s)}$ states, we study their hidden-strange analogues $P_s$ states in both $[udu][\bar ss]$ and $[uds][\bar su]$ configurations. We investigate the $P_s$ pentaquark states in $p\eta^\prime$, $p\phi$, $\Lambda K$, $\Sigma K$ and $\Sigma^\ast K^\ast$ structures with $J^P = \frac{1}{2}^-$ and $\Sigma ^\ast K$ and $\Sigma K^\ast$ with $J^P = \frac{3}{2}^-$, and calculate their masses in the framework of QCD sum rules. Our numerical results show that the extracted hadron masses for all the $p\eta^\prime$, $p\phi$, $\Lambda K$, $\Sigma K$ and $\Sigma^\ast K^\ast$ structures are much higher than $\Sigma K$ mass threshold and masses for $\Sigma ^\ast K$ and $\Sigma K^\ast$ also higher than threshold of corresponding hadron, so that no bound state exists in such channels, which is consistent with the experimental status to date.Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.

D-wave excited tetraquark states with and *

“…). Similar results were obtained for the fully heavy tetraquark states [56][57][58]. However, the situation is different for the excited tetraquarks: the masses of color antisymmetric tetraquarks are lower than those of color symmetric tetraquarks.…”