Paper

Heavy quark spin partners of the \\(Y(4260)\\) in coupled-channel formalism

Lu, Yu, Muhammad Naeem Anwar

2021

Overview

The charmoniumlike state \\(Y(4260)\\) is described as predominantly a \\(D_1 \\bar{D}\\) molecule in a coupled-channel quark model [Phys.\\,Rev.\\,D\\,\\textbf{96},\\,114022\\,(2017)]. The heavy quark spin symmetry (HQSS) thus implies the possible emergence of its heavy quark spin partners with molecular configuration as \\(D_1 \\bar{D}^*\\) and \\(D_2^* \\bar{D}^*\\) below these charmed mesons' thresholds. We analyze the probabilities of various intermediate charmed meson loops for \\(J^{PC}=1^{--}\\) exotic state \\(Y(4360)\\) and find that the channel \\(D_1 \\bar{D}^*\\) couples more strongly around its mass regime, and the coupling behavior remains the same even if the mass of \\(Y(4360)\\) is pushed closer to \\(D_1 \\bar{D}^*\\) threshold. This enlightens that the most favorable molecular scenario for the \\(Y(4360)\\) could be \\(D_1 \\bar{D}^*\\), and hence it can be interpreted as HQSS partner of the \\(Y(4260)\\). We also find the strong coupling behavior of \\(D_2^* \\bar{D}^*\\) channel with the \\(\\psi(4415)\\), which makes it a good candidate for a dominant \\(D_2^* \\bar{D}^*\\) molecule. We discuss the important decay patterns of these resonances to disentangle their long- and short-distance structures.

• Publisher: Cornell University Library, arXiv.org
• Subject: Charm (particle physics) / Coupling (molecular) / Mesons / Quark models / Quarks