QCD SUM-RULES FOR NUCLEONS IN NUCLEAR-MATTER-III

The self-energies of quasinucleon states in nuclear matter are investigated using a finite-density QCD sum-rule approach developed previously. The sum rules are obtained for a general QCD interpolating field for the nucleon. The key phenomenological inputs are the nucleon sigma term, the strangeness content of the nucleon, and quark and gluon distribution functions deduced from deep-inelastic scattering. The emphasis is on testing the sensitivity and stability of sum-rule predictions to variations of the condensates and other input parameters. At nuclear matter saturation density, the Lorentz vector self-energy is found to be positive with a magnitude of a few hundred MeV, which is comparable to that suggested by relativistic nuclear phenomenology This result is quite stable. The prediction for the scalar self-energy is very sensitive to the undetermined values of the in-medium four-quark condensates.