ar X iv : h ep - p h / 96 10 42 8 v 1 2 1 O ct 1 99 6 RPA - Approach to the Excitations of the Nucleon , Part II : Phenomenology
نویسندگان
چکیده
The tensor-RPA approach developed previously in part I is applied to the Nambu-Jona-Lasinio (NJL) model. As a first step we investigate the structure of Dirac-Hartree-Fock solutions for a rotationally and isospin invariant ground-state density. Whereas vacuum properties can be reproduced, no soli-tonic configuration for a system with unit baryon number is found. We then solve the tensor-RPA equation for a class of simple models of the nucleon ground state. In general the ph interaction effects a decrease of the excited states to lower energies. Strong ground-state correlations are found in the vacuum sector. Due to the enhanced level density and the incorrect ordering of parities the obtained spectra cannot be matched with the experimental data. The results indicate that a mean field + RPA approach is likely to be insufficient for the description of baryon spectra in general.
منابع مشابه
ar X iv : h ep - p h / 96 05 29 9 v 1 1 4 M ay 1 99 6 RPA - Approach to the Excitations of the Nucleon Part I : Theory
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تاریخ انتشار 1996