Spectra of anti-nucleons in the vacuum of finite nuclei

Abstract

The quantum vacuum in a many-body system of finite nuclei has been investigated within the relativistic Hartree approach which describes the bound states of nucleons and anti-nucleons consistently. The contributions of the Dirac sea to the source terms of the meson-field equations are taken into account up to the one-nucleon loop and one-meson loop. The tensor couplings for the $ω$- and $ρ$-meson are included in the model. After adjusting the parameters of the model to the properties of spherical nuclei, a large effective nucleon mass $m^{*}/M_{N} \approx 0.78$ is obtained. The overall nucleon spectra of shell-model states are in agreement with the data. The computed anti-nucleon spectra in the vacuum differ about 20 -- 30 MeV with and without the tensor-coupling effects.

12 pages, 2 postscript files included. Proceeding of the 2003 Dalian International Symposium on Nuclear Physics, to appear on High Energy Physics and Nuclear Physics