We study nuclear matter and finite nuclei in the mean field approximation 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 π fields as well as the glueball field φ. The scale invariant term which leads to an omega meson mass, after symmetry breaking, is strongly favored to be of the form ωμωμφ2 by the bulk properties of nuclei; they also rather strongly constrain the other parameters. A reasonable description of the closed shell nuclei oxygen, calcium and lead can be achieved and this can be improved by including a term(ωμmωμm)2 in the lagrangian. This leads to a level of agreement with the data that is comparable to that of the nonlinear Walecka model.
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We thank G.F. Bertsch and A. Vischer for useful comments and C.J. Horowitz for giving us a copy of his computer code for finite nuclei which was suitably modified for presentp urposes.O ne of us (PJE) is gratefulf or the hospitality provided by the Institute for Theoretical Physics of the University of California at Santa Barbara where a portion of this work was carried out. We acknowledgep artial support from the Departmento f Energy under contractsN o. DE-FG02-87ER40328 and DE-AC02-83ER40105. A grant for computing time from the Minnesota SupercomputerI nstitute is gratefullya cknowledged.
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