QCD sum rules for nucleons in nuclear matter II

Abstract

A correlator of QCD interpolating fields for the nucleon is evaluated in nuclear matter by applying an operator product expansion. All density dependence is incorporated into the composite operator matrix elements (condensates) taken in the nuclear matter ground state. The in-medium condensates up to dimension five are estimated to first order in the nucleon density. The key phenomenological inputs used in determining the quark and gluon condensates up to dimension four are the nucleon \ensuremath{\sigma} term, the strangeness content of the nucleon, and quark and gluon distribution functions deduced from deep-inelastic scattering experiments. Dimension-five quark and quark-gluon condensates, which give small contributions to the correlator, are estimated by a variety of techniques. Contributions from dimension-six four-quark condensates are also included in a factorized form.