Is the existence of a J/ψJ/ψ bound state plausible?

Xiang-Kun Dong; Vadim Baru; Feng-Kun Guo; Christoph Hanhart; Alexey Nefediev; Bing-Song Zou

doi:10.1016/j.scib.2021.09.009

Is the existence of a J/ψJ/ψ bound state plausible?

Sci Bull (Beijing). 2021 Dec 30;66(24):2462-2470. doi: 10.1016/j.scib.2021.09.009. Epub 2021 Sep 16.

Authors

Xiang-Kun Dong¹, Vadim Baru², Feng-Kun Guo³, Christoph Hanhart⁴, Alexey Nefediev⁵, Bing-Song Zou⁶

Affiliations

¹ 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. Electronic address: dongxiangkun@itp.ac.cn.
² Institut für Theoretische Physik II, Ruhr-Universität Bochum, Bochum D-44780, Germany; Institute for Theoretical and Experimental Physics NRC "Kurchatov Institute", Moscow 117218, Russia. Electronic address: vadim.baru@tp2.rub.de.
³ 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. Electronic address: fkguo@itp.ac.cn.
⁴ Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, Jülich D-52425, Germany. Electronic address: c.hanhart@fz-juelich.de.
⁵ P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow 119991, Russia; Moscow Institute of Physics and Technology, Moscow 141700, Russia. Electronic address: nefediev@lebedev.ru.
⁶ 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; School of Physics, Central South University, Changsha 410083, China.

PMID: 36654205
DOI: 10.1016/j.scib.2021.09.009

Abstract

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_ψ(2S)J/ψ|=(1.8±0.1)GeV^-3, where the uncertainty also includes the one induced by the final state interactions.

Keywords: Dispersion relation; Exotic hadron; Fully-charm tetraquark; Hadronic molecule.

MeSH terms

Electricity*
Existentialism
Mesons*
Uncertainty