- Open Access
Meson-nucleus bound states with neural-network quantum states
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 -, -, and -nucleus ground states up to mass number based on the HAL QCD meson-nucleon potentials at near-physical point. The ()-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 to yields ground-state energies consistent with the experiment. Meson-nucleus bound states emerge at for , for , and for . The -nucleus systems exhibit the strongest binding, with binding energies reaching tens of MeV. The -nucleus and -nucleus systems are weakly bound at the few-MeV and sub-MeV scale, respectively. The binding energy per nucleon deepens nearly linearly with for charmonium systems, whereas the -nucleus system exhibits a nonmonotonic behavior peaking at —a distinctive hallmark of the short-range and strongly attractive 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 . 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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