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arXiv · 2009.08376

Perturbative QCD Evidence for Spin-2 Particles in the Di-$J/\psi$ Resonances

Hong-Fei Zhang·Yan-Qing Ma·Wen-Long Sang
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Abstract

We extend the nonrelativistic QCD framework to explore the nature of the newly discovered di-$J/\psi$ resonances. Assuming them as either molecule-like states or tetraquarks, we calculated their hadroproduction cross sections at the LHC. We find that the observed resonances are most likely spin-2 particles, and there should exist their spin-0 counterparts near these resonances. The ratio of production cross sections of the observed resonances to the latent spin-0 ones are also presented, which might help to distinguish molecule-like states from tetraquarks.

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Hong-Fei Zhang, Yan-Qing Ma, Wen-Long Sang. 2020-09-17. Perturbative QCD Evidence for Spin-2 Particles in the Di-$J/\psi$ Resonances. https://doi.org/10.1016/j.scib.2025.04.035

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