QCD sum rules for hyperons in nuclear matter

Abstract

Using a finite-density QCD sum-rule approach, we investigate the self-energies of Λ and ∑ hyperons propagating in uniform nuclear matter. We find that the Lorentz vector self-energy of the Λ is substantially smaller than the corresponding nucleon self-energy and the vector self-energy of the ∑ is similar to the nucleon vector self-energy. The Lorentz scalar self-energies, sensitive to the density dependence of certain condensates, tend to cancel the vector self-energies, but not completely.