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 $cc\overline{c}\overline{c}$ tetraquarks.

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相对论夸克模型中的重四夸克

我们回顾了在相对论夸克模型框架下基于准势方法和QCD的具有两个和四个重夸克的四夸克质量的计算。使用了重夸克的diquark-antidiquark图片。夸克-夸克和双夸克-反双夸克相互作用的准势的构造与先前对介子和重子的考虑类似。双夸克被认为是三色态。假设双夸克和反双夸克在整个四夸克中相互作用，并且通过计算的双夸克-胶子相互作用的形状因子考虑了双夸克的内部结构。根据我们先前对介子和重子特性的计算，模型的所有参数均保持不变。给出了获得的重夸克质量预测与现有实验数据的详细比较。发现了四夸克的许多候选物。有人认为，二元结构$Ĵ/\psi$ LHCb合作最近观察到的质谱可以解释为 $CC\overline{C}\overline{C}$ 四夸克。