Observation of the $T_{c\bar{c}1}(4430{)}^{-}$ state in $B^0\to D^{\ast -}{D}^0{K}^{+}$ decays

Abstract

A study of resonant structures in $B^0\to D^{\ast -}{D}^0{K}^{+}$ decays is presented. The analysis uses proton-proton collision data collected by the LHCb experiment at center-of-mass energies of $\sqrt{s}=7$, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb${}^{-1}$. The analysis demonstrates that the existing known excited $D_s^{+}$ resonances in the $D^0{K}^{+}$ spectrum are insufficient to describe the data. The inclusion of the tetraquark state $T_{c\bar{c}1}(4430{)}^{-}$ improves the description of the data with a statistical significance exceeding $5\sigma$. This corresponds to the first observation of the $T_{c\bar{c}1}(4430{)}^{-}\to D^{\ast -}{D}^0$ decay. The measured properties of the $T_{c\bar{c}1}(4430{)}^{-}$ state are consistent with those previously measured in its decay to the $\psi (2S){\pi }^{-}$ final state.

arXiv commentAll figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://lhcb-glance.cern.ch/alcm/public/analysis/full-details/3991/ (LHCb public pages)