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Nucleon QCD sum rules in nuclear matter including four-quark condensates

E. G. Drukarev·M. G. Ryskin·V. A. Sadovnikova·Th. Gutsche·Amand Faessler
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Abstract

We calculate the nucleon parameters in nuclear matter using the QCD sum rules approach in Fermi gas approximation. Terms up to 1/q^2 in the operator product expansion (OPE) are taken into account. The higher moments of the nucleon structure functions are included. The complete set of the nucleon expectation values of the four-quark operators is employed. Earlier the lack of information on these values has been the main obstacle for the further development of the approach. We show that the four-quark condensates provide the corrections of the order 20% to the results obtained in the leading orders of the OPE. This is consistent with the assumption about the convergence of the OPE. The nucleon vector self-energy Σ_v and the nucleon effective mass m^* are expressed in terms of the in-medium values of QCD condensates. The numerical results for these parameters at the saturation value of the density agree with those obtained by the methods of nuclear physics.

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E. G. Drukarev, M. G. Ryskin, V. A. Sadovnikova, Th. Gutsche, Amand Faessler. 2004-06-17. Nucleon QCD sum rules in nuclear matter including four-quark condensates. https://doi.org/10.1103/physrevc.69.065210

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