Analysis of the axialvector doubly-charmed tetraquark molecular states with the QCD sum rules

In the present work, we investigate the axialvector doubly-charmed tetraquark molecular states without strange, with strange and with doubly-strange via the QCD sum rules, and try to make assignment of the $T^+_{cc}$ from the LHCb collaboration in the scenario of molecular states. The predictions favor assigning the $T^+_{cc}$ to be the heavier $DD^{*}$ molecular state with the spin-parity $J^P=1^+$, while the lighter $DD^{*}$ molecular state with the spin-parity $J^P=1^+$ still escapes experimental detections. All the predicted doubly-charmed tetraquark molecular states can be confronted to the experimental data in the future.