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arXiv · 2610.29861

Progress on meson-glueball mixing in lattice gauge theories coupled to fermions in multiple representations

Nuno Brito·Ed Bennett·Deog Ki Hong·Jong-Wan Lee·C. -J. David Lin·Biagio Lucini·Maurizio Piai·Davide Vadacchino·Fabian Zierler
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Abstract

We present preliminary results from our numerical lattice investigation of the low-lying flavour-singlet bound states in the ${\rm Sp}(4)$ gauge theory coupled to fermions transforming in the fundamental and two-index antisymmetric representations. We use the Wilson gauge action and Wilson fermions. We employ the generalized eigenvalue problem (GEVP) method with a basis of smeared glueball and meson interpolating operators. We analyse two high-statistics ensembles with the same lattice coupling and different fermion mass. We study both the scalar and pseudoscalar states. We observe the first evidence for meson-glueball mixing in this theory. We improve upon previous determinations of the energy eigenstates and mixing angles in the flavour-singlet pseudoscalar sector.

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Nuno Brito, Ed Bennett, Deog Ki Hong, Jong-Wan Lee, C. -J. David Lin, Biagio Lucini, Maurizio Piai, Davide Vadacchino, Fabian Zierler. 2026-10-21. Progress on meson-glueball mixing in lattice gauge theories coupled to fermions in multiple representations. https://arxiv.org/abs/2610.29861

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