Scalar and vector decomposition of the nucleon self-energy in the relativistic Brueckner approach

Abstract

We investigate the momentum dependence of the nucleon self-energy in nuclear matter. We apply the relativistic Brueckner-Hartree-Fock approach and adopt the Bonn A potential. A strong momentum dependence of the scalar and vector self-energy components can be observed when a commonly used pseudo-vector choice for the covariant representation of the T-matrix is applied. This momentum dependence is dominated by the pion exchange. We discuss the problems of this choice and its relations to on-shell ambiguities of the T-matrix representation. Starting from a complete pseudo-vector representation of the T-matrix, which reproduces correctly the pseudo-vector pion-exchange contributions at the Hartree-Fock level, we observe a much weaker momentum dependence of the self-energy. This fixes the range of the inherent uncertainty in the determination of the scalar and vector self-energy components. Comparing to other work, we find that extracting the self-energy components by a fit to the single particle potential leads to even more ambiguous results.

35 pages RevTex, 7 PS figures, replaced by a revised and extended version

References in corpus (4)

• Relativistic Brueckner-Hartree-Fock calculations with explicit intermediate negative energy states
• Nucleon self-energy in the relativistic Brueckner approach
• Relativistic Structure of the Nucleon Self-Energy in Asymmetric Nuclei
• Momentum Dependence of Single Particle Potential in Dirac Brueckner Approach

Cited by in corpus (14)

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• Off shell behaviour of the in medium nucleon-nucleon cross section
• 1S0 Proton and Neutron Superfluidity in beta-stable Neutron Star Matter
• Nuclear matter in relativistic Brueckner-Hartree-Fock theory with Bonn potential in the full Dirac space
• Differential Flow of Protons in Au+Au Collisions at AGS Energies
• Heavy ion collisions with non-equilibrium Dirac-Brueckner mean fields
• The relativistic self-energy in nuclear dynamics
• Neutron-proton effective mass splitting in neutron-rich matter
• Properties of nuclear matter in relativistic Brueckner-Hartree-Fock model with high-precision charge-dependent potentials
• The charge-dependent Bonn potentials with pseudovector pion-nucleon coupling
• Nuclear Matter Equation of State and Three body Forces