A study of the decays of \(S-\)wave \(\bar D^\ast K^\ast\) hadronic molecules: the scalar \(X_0(2900)\) and its spin partners \(X_{J(J=1,2)}\)

• Published in: arXiv.org
• Main Authors: Cheng-Jian, Xiao, Dian-Yong, Chen, Yu-Bing, Dong, Guang-Wei Meng
• Format: Paper
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 30.09.2020
• Subjects: Decay
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2009.14538

In this work, we investigated the decays of the fully open-flavor tetraquark state \(X_0(2900)\) which was observed by the LHCb Collaboration very recently. Here, the \(X_0(2900)\) was assigned as a \(S-\)wave \(\bar D^\ast K^\ast\) hadronic molecule with \(I=0\), and the effective lagrangian approach was applied to estimate the partial decay widths. Moreover, we also predicted the decay behaviors of the other unobserved \(X_{J(J=1,2)}\), which were the spin partners of the \(X_0(2900)\) in the \(S-\)wave \(\bar D^\ast K^\ast\) picture. It was pointed out that the \(X_1\) state with \(I=0\) was a broad state with the width more than one hundred MeV, while another \(X_2\) state with \(I=0\) was a narrow state with the width approaching half of that for the \(X_0(2900)\). In addition, our results also showed that the \(\bar D^\ast K\) mode was expected to be the dominant decay mode for both \(X_1\) and \(X_2\). Searching for those unobserved \(X_{J(J=1,2)}\) in the future experiments might be helpful to understand the nature of \(X_0(2900)\).