Speaker
Description
In 2021, the LHCb Collaboration discovered the first doubly charmed tetraquark state $ T_{cc}(3875)^+ $, which may open a new chapter for the discovery of other doubly heavy exotic states in the future. We investigate the S-wave doubly heavy tetraquark systems, including the $ QQ^{(\prime)}\bar q\bar q $, $ QQ^{(\prime)}\bar s\bar q $, and $ QQ^{(\prime)}\bar s\bar s $ ($ Q^{(\prime)}=b,c $ and $ q=u,d $) systems, within the constituent quark model. Besides the $ D^*D $ molecular bound state as a candidate of $ T_{cc}(3875)^+ $, we also obtain a series of other bound and resonant states with various configurations, including meson molecules, compact diquark-antidiquark tetraquarks, compact even tetraquarks (QCD analog of hydrogen molecule) and compact diquark-centered tetraquarks (QCD analog of helium atom). The classifications of tetraquarks based on their color-spatial configurations help unravel the rich internal structures and various forming mechanisms of tetraquark states.
