Dong Xiang-Kun, Baru Vadim, Guo Feng-Kun, Hanhart Christoph, Nefediev Alexey, Zou Bing-Song
CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
Institut für Theoretische Physik II, Ruhr-Universität Bochum, Bochum D-44780, Germany; Institute for Theoretical and Experimental Physics NRC "Kurchatov Institute", Moscow 117218, Russia.
Sci Bull (Beijing). 2021 Dec 30;66(24):2462-2470. doi: 10.1016/j.scib.2021.09.009. Epub 2021 Sep 16.
In a recent measurement LHCb reported pronounced structures in the J/ψJ/ψ spectrum. One of the various possible explanations of those is that they emerge from non-perturbative interactions of vector charmonia. It is thus important to understand whether it is possible to form a bound state of two charmonia interacting through the exchange of gluons, which hadronise into two pions at the longest distance. In this paper, we demonstrate that, given our current understanding of hadron-hadron interactions, the exchange of correlated light mesons (pions and kaons) is able to provide sizeable attraction to the di-J/ψ system, and it is possible for two J/ψ mesons to form a bound state. As a side result we find from an analysis of the data for the ψ(2S)→J/ψππ transition including both ππ and KK¯ final state interactions an improved value for the ψ(2S)→J/ψ transition chromo-electric polarisability: |α|=(1.8±0.1)GeV, where the uncertainty also includes the one induced by the final state interactions.
在最近的一次测量中，大型强子对撞机底夸克实验（LHCb）报告了J/ψJ/ψ谱中明显的结构。对这些结构的各种可能解释之一是，它们源自矢量粲夸克偶素的非微扰相互作用。因此，了解通过胶子交换相互作用的两个粲夸克偶素是否有可能形成束缚态很重要，胶子在最长距离处强子化为两个π介子。在本文中，我们证明，基于我们目前对强子 - 强子相互作用的理解，相关轻介子（π介子和K介子）的交换能够为双J/ψ系统提供可观的吸引力，并且两个J/ψ介子有可能形成束缚态。作为附带结果，我们通过对ψ(2S)→J/ψππ跃迁的数据进行分析，包括ππ和KK¯末态相互作用，得到了ψ(2S)→J/ψ跃迁色电极化率的改进值：|α|=(1.8±0.1)GeV，其中不确定性还包括末态相互作用引起的不确定性。
