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arXiv · 1012.0394

A New Approach to Physics of Nuclei

E. G. Drukarev·M. G. Ryskin·V. A. Sadovnikova
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Abstract

We employ the QCD sum rules method for description of nucleons in nuclear matter. We show that this approach provides a consistent formalism for solving various problems of nuclear physics. Such nucleon characteristics as the Dirac effective mass $m^*$ and the vector self-energy $Σ_V$ are expressed in terms of the in-medium values of QCD condensates. The values of these parameters at saturation density and the dependence on the baryon density and on the neutron-to-proton density ratio is in agreement with the results, obtained by conventional nuclear physics method. The contributions to $m^*$ and $Σ_V$ are related to observables and do not require phenomenological parameters. The scalar interaction is shown to be determined by the pion--nucleon $σ$-term. The nonlinear behavior of the scalar condensate may appear to provide a possible mechanism of the saturation. The approach provided reasonable results for renormalization of the axial coupling constant, for the contribution of the strong interactions to the neutron--proton mass difference and for the behavior of the structure functions of the in-medium nucleon. The approach enables to solve the problems which are difficult or unaccessible for conventional nuclear physics methods. The method provides guide-lines for building the nuclear forces. The three-body interactions emerge within the method in a natural way. There rigorous calculation will be possible in framework of self-consistent calculation in nuclear matter of the scalar condensate and of the nucleon effective mass $m^*$.

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E. G. Drukarev, M. G. Ryskin, V. A. Sadovnikova. 2012-12-24. A New Approach to Physics of Nuclei. https://doi.org/10.1134/s1063778811080047

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