Masses and magnetic moments of exotic fully heavy pentaquarks

Inspired by the observation of a resonant state X(6600) of fully charm tetraquark by theCMSexperiment of LHCb Collaboration in double J/Psi decay channel, we perform a systematical study of all configurations of fully heavy pentaquarks P-Q1Q2Q3Q4 Q5 ( Qi = c, b, i = 1, 2, 3, 4, 5) in their ground states in unified framework of MIT bag model. The color-spin wavefunctions of pentaquarks, classified via Young tableau and presented in terms of the YoungYamanouchi bases, are used to computemasses and magnetic moments of fully heavy pentaquarks via numerical variational method, predicting a set of masses ranging from 8.229 GeV for the P-cccc c to 24.770 GeV for the P-bbbb b. Combining with computed masses of fully heavy mesons and baryons, we find that masses of fully heavy hadrons(mesons, baryons, tetraquarks and pentaquarks) with identical flavor rise almost linearly with the number of valence quarks in hadrons, being consistent with the heavy quark symmetry in the heavy-quark limit.

Automated summary

Inspired by the observation of a resonant state X(6600) of fully charm tetraquark by the CMS experiment of LHCb Collaboration in double J/Psi decay channel, this study systematically investigates all configurations of fully heavy pentaquarks in MIT bag model and computes their masses and magnetic moments. The results show a linear relationship between the masses of fully heavy hadrons with identical flavor and the number of valence quarks in hadrons, consistent with heavy quark symmetry.