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arXiv · 2411.11533

Lattice calculation of the $\eta_c\eta_c$ and $J/\psi J/\psi$ s-wave scattering length

Yu Meng·Chuan Liu·Xin-Yu Tuo·Haobo Yan·Zhaolong Zhang
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Abstract

We calculate the s-wave scattering length in the $0^+$ sector of $\eta_c\eta_c$ and the $2^+$ sector of $J/\psi J/\psi$ using three $N_f=2$ twisted mass gauge ensembles with the lattice spacing $a=0.0667,0.085,0.098$ fm, respectively. The scattering lengths are extracted using the conventional L{\"u}scher finite size method. We observe sizable discretization effects and the results after a continuum extrapolation are $a^{0^+}_{\eta_c\eta_c}=-0.104(09)$ fm and $a^{2^+}_{J/\psi J/\psi}=-0.165(16)$ fm. The slight difference of light quark mass is ignored in this study. Our results indicate that the interaction between the two respective charmonia are repulsive in nature in both cases.

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Yu Meng, Chuan Liu, Xin-Yu Tuo, Haobo Yan, Zhaolong Zhang. 2024-11-18. Lattice calculation of the $\eta_c\eta_c$ and $J/\psi J/\psi$ s-wave scattering length. https://arxiv.org/abs/2411.11533

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