Heavy Tetraquarks in the Relativistic Quark Model

We give a review of the calculations of the masses of tetraquarks with two and four heavy quarks in the framework of the relativistic quark model based on the quasipotential approach and QCD. The diquark-antidiquark picture of heavy tetraquarks is used. The quasipotentials of the quark-quark and diquark-antidiquark interactions are constructed similarly to the previous consideration of mesons and baryons. Diquarks are considered in the colour triplet state. It is assumed that the diquark and antidiquark interact in the tetraquark as a whole and the internal structure of the diquarks is taken into account by the calculated form factor of the diquark-gluon interaction. All parameters of the model are kept fixed from our previous calculations of meson and baryon properties. A detailed comparison of the obtained predictions for heavy tetraquark masses with available experimental data is given. Many candidates for tetraquarks are found. It is argued that the structures in the di-J/psi mass spectrum observed recently by the LHCb collaboration can be interpreted as ccc over bar c over bar tetraquarks.

Automated summary

The masses of tetraquarks with two and four heavy quarks were calculated in the relativistic quark model using the quasipotential approach and QCD, based on the diquark-antidiquark picture. A comparison with experimental data revealed numerous candidates for tetraquarks, with the recent structures observed in the di-J/psi mass spectrum potentially corresponding to ccc over bar c over bar tetraquarks.