Doubly heavy tetraquarks in a chiral-diquark picture

Doubly heavy tetraquarks in a chiral-diquark picture

Energy spectrum of doubly heavy tetraquarks, T QQ ( QQ ¯ q ¯ q with Q = c, b and q = u, d, s ), is studied in the potential chiral-diquark model. Using the chiral effective theory of diquarks and the quark-diquark-based potential model, the T bb , T cc , and T cb tetraquarks are described as a three-body system composed of two heavy quarks and an antidiquark. We find several T bb bound states, while no T cc and T cb (deep) bound state is seen. We also study the change of the T QQ tetraquark masses under restoration of chiral symmetry.

在势手征双夸克模型中研究了双重味四夸克的能谱，$T_{QQ}$（$QQ\bar{q}\bar{q}$，其中$Q = c,b$且$q = u,d,s$）。利用双夸克的手征有效理论以及基于夸克 - 双夸克的势模型，将$T_{bb}$、$T_{cc}$和$T_{cb}$四夸克描述为由两个重夸克和一个反双夸克组成的三体系统。我们发现了几个$T_{bb}$束缚态，然而没有看到$T_{cc}$和$T_{cb}$（深）束缚态。我们还研究了在手征对称性恢复的情况下$T_{QQ}$四夸克质量的变化。