Doubly heavy tetraquark multiplets as heavy antiquark-diquark symmetry partners of heavy baryons

Abstract

Symmetries play important roles in the understanding of hadron structures and spectroscopy. Motivated by the discovery of the doubly charmed tetraquark ${T}_{cc}^{+}(3875)$, we study the ground states of the doubly heavy tetraquarks with the QCD inspired heavy antiquark-diquark symmetry in the constituent quark model. Six ground states of ${T}_{QQ}(Q=c,b)$ are predicted and the lightest ${T}_{cc}$ state has a mass of $3875.8\ifmmode\pm\else\textpm\fi{}7.6\text{ }\text{ }\mathrm{MeV}$ and spin-parity ${1}^{+}$, which are consistent with those of the observed ${T}_{cc}^{+}(3875)$. In addition, the magnetic moments of the predicted tetraquarks ${T}_{cc}^{+}(3876)$ and ${T}_{bb}^{\ensuremath{-}}(10396)$ are also estimated in the same model, which provide further information to distinguish the structures of the ${T}_{QQ}$ states.