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arXiv · 2507.19872

Comment on "Improved measurement of $\eta/\eta'$ mixing in $B_{(s)}^0\to J/\psi \eta^{(\prime)}$ decays"

Ying Chen·Geng Li
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Abstract

Instead of the glueball-$\eta'$ mixing ansatz, the latest measured ratios of the branching fractions of $B_{(s)}^0\to J/\psi \eta^{(\prime)}$ decays by LHCb can be understood by including the contribution from the light quark annihilation effect enhanced by the QCD $\mathrm{U}_A(1)$ anomaly for light pseudoscalar mesons.

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Ying Chen, Geng Li. 2025-07-26. Comment on "Improved measurement of $\eta/\eta'$ mixing in $B_{(s)}^0\to J/\psi \eta^{(\prime)}$ decays". https://arxiv.org/abs/2507.19872

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