Spectroscopy and decays of the fully-heavy tetraquarks

Abstract

Abstract We discuss the possible existence of the fully-heavy tetraquarks. We calculate the ground-state energy of the $$bb {\bar{b}} {\bar{b}}$$ bbb¯b¯ bound state, where b stands for the bottom quark, in a nonrelativistic effective field theory framework with one-gluon-exchange (OGE) color Coulomb interaction, and in a relativized diquark model characterized by OGE plus a confining potential. Our analysis advocates the existence of uni-flavor heavy four-quark bound states. The ground state $$bb{\bar{b}}{\bar{b}}$$ bbb¯b¯ tetraquark mass is predicted to be $$(18.72\pm 0.02)$$ (18.72±0.02) GeV. Mass inequality relations among the lowest $$QQ\bar{Q}\bar{Q}$$ QQQ¯Q¯ states, where $$Q\in \{c, b\}$$ Q∈{c,b} , and the corresponding heavy quarkonia are presented, which give the upper limit on the mass of ground state $$QQ\bar{Q}\bar{Q}$$ QQQ¯Q¯ . The possible decays of the lowest $$bb\bar{b}\bar{b}$$ bbb¯b¯ are highlighted, which might provide useful references in the search for them in ongoing LHC experiments, and its width is estimated to be a few tens of MeV.