Evidence of the open-flavor tetraquark $T_{c\bar{s}2}$ in the process $B^+\to D^{*-}D_s^+π^+$

Abstract: The newly observed open-flavor tetraquark $T_{c\bar{s}0}(2900)$ has attracted many attentions, and searching for its spin partners is crucial to exploring the internal structure of those states. In this work, we will show that, the $D_s^+\pi^+$ invariant mass distribution of the process $B^+\to D^{*-}D_s^+\pi^+$ measured by LHCb has a resonant-like structure around 2830~MeV, which could be associated with the predicted $T_{c\bar{s}2}$, the spin $J=2$ partner of $T_{c\bar{s}0}(2900)$. Furthermore, we have evaluated the momenta of the angular mass distribution, which are very different for each of the spin assumptions, and have larger strength at the resonant energy than the peaks seen in the angular integrated mass distribution. We make a call for the experimental determination of these magnitudes, which could be used to pin down the existence of the $T_{c\bar{s}2}$.