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An Effective Lagrangian with Broken Scale and Chiral Symmetry Applied to Nuclear Matter and Finite Nuclei

E. K. Heide·S. Rudaz·P. J. Ellis
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Abstract

We study nuclear matter and finite nuclei with a chiral Lagrangian which generalizes the linear $σ$ model and also accounts for the QCD trace anomaly by means of terms which involve the $σ$ and $\vmgπ$ fields as well as the glueball field $ϕ$. The form of the scale invariant term leading to an omega meson mass, after symmetry breaking, could involve coupling to $ϕ^2$ or $σ^2$ or some linear combination thereof. In fact an $ω_μω^μϕ^2$ form is strongly favored by the bulk properties of nuclei, which also rather strongly constrain the other parameters. A reasonable description of the closed shell nuclei oxygen, calcium and lead can be achieved, although the spin-orbit splittings are somewhat smaller than the experimental values.

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E. K. Heide, S. Rudaz, P. J. Ellis. 1993-08-02. An Effective Lagrangian with Broken Scale and Chiral Symmetry Applied to Nuclear Matter and Finite Nuclei. https://doi.org/10.1016/0375-9474(94)90717-x

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