Abstract
The fully heavy pentaquarks $cccc\bar{c}$ and $bbbb\bar{b}$ are systematically investigated within the chiral quark model and quark delocalization color screening model. The results are consistent in both two moelds, and the effect of the channel-coupling is crucial for forming a bound state of the fully heavy pentaquark system. Three possible fully heavy pentaquarks are obtained, which are the $cccc\bar{c}$ state with $J^P = 1/2^-$ and the mass of $7891.9 \sim 7892.7$ MeV, the $bbbb\bar{b}$ state with $J^P=1/2^-$ and the mass of $23810.1 \sim 23813.8$ MeV, and the $bbbb\bar{b}$ state with $J^P = 3/2^-$ and the mass of $23748.2 \sim 23752.3$ MeV. All these fully heavy pentaquark states are worth searching in future experiments.
Highlights
Over the past decades, great progress has been made on studying exotic states, among which the fully heavy tetraquark states ðQQQ Q ; Q 1⁄4 c; bÞ attracted extensive attention, since such states with very large energy can be accessed experimentally and distinguished from other states
The molecular configurations for the fully charm tetraquark states were proposed by the perturbation QCD [9], while the compact structure was obtained in the holography inspired stringy hadron model [10]
We investigate the S-wave fully heavy pentaquark systems cccccand bbbbbin the framework of two quark models, the chiral quark model (ChQM) and the quark delocalization color screening model (QDCSM)
Summary
Great progress has been made on studying exotic states, among which the fully heavy tetraquark states ðQQQ Q ; Q 1⁄4 c; bÞ attracted extensive attention, since such states with very large energy can be accessed experimentally and distinguished from other states. The LHCb Collaboration updated their results, a new state Pcð4312Þ was proposed, and the Pcð4450Þ was split into Pcð4440Þ and Pcð4457Þ states [21] These observations of the hidden-charm pentaquarks bring great interest in theoretical investigations. An alternative approach is the quark delocalization color screening model (QDCSM), which was developed in the 1990s with the aim of explaining the similarities between nuclear and molecular forces [32] Both of the models have been successfully applied to the study of the properties of deuteron, nucleon-nucleon, and hyperonnucleon interactions [33,34].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
