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Meson-nucleus bound states with neural-network quantum states

Wei-Lin Wu1,*, Liang-Zhen Wen1,†, and Shi-Lin Zhu2,‡

  • *Contact author: wlwu@pku.edu.cn
  • †Contact author: wenlzh_hep-th@stu.pku.edu.cn
  • ‡Contact author: zhusl@pku.edu.cn

Phys. Rev. D 114, 054060 – Published 30 September, 2026

DOI: https://doi.org/10.1103/3nrk-c5c7

Abstract

We present the first systematic calculations of ϕ-, ηc-, and J/ψ-nucleus ground states up to mass number A=12 based on the HAL QCD meson-nucleon potentials at near-physical point. The (A+1)-body Schrödinger equation is solved with a neural-network variational Monte Carlo framework, generalized to incorporate mesonic degrees of freedom. Benchmarking on light nuclei from H2 to C12 yields ground-state energies consistent with the experiment. Meson-nucleus bound states emerge at A≥2 for ϕ, A≥4 for J/ψ, and A≥6 for ηc. The ϕ-nucleus systems exhibit the strongest binding, with binding energies reaching tens of MeV. The J/ψ-nucleus and ηc-nucleus systems are weakly bound at the few-MeV and sub-MeV scale, respectively. The binding energy per nucleon deepens nearly linearly with A for charmonium systems, whereas the ϕ-nucleus system exhibits a nonmonotonic behavior peaking at He4—a distinctive hallmark of the short-range and strongly attractive ϕN interaction. The meson compresses the nucleon distribution relative to the parent nucleus, and evolves from a halo configuration to one embedded inside the nucleus with increasing A. Our results provide predictions for future experimental searches, and establish a quantitative bridge between lattice QCD meson-nucleon interactions and the emergent many-body phenomena in meson-nucleus bound states.

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