The structure of nucleon self-energy in nuclear matter is evaluated for various realistic models of the nucleon-nucleon (NN) interaction. Starting from the Brueckner-Hartree-Fock approximation without the usual angle-average approximation, the effects of hole-hole contributions and a self-consistent treatment within the framework of the Green function approach are investigated. Special attention is paid to the predictions for the spectral function originating from various models of the NN interaction which all yield an accurate fit for the NN phase shifts.

Starting from the presence of non-ideal plasma effects due to strongly coupled plasma in the early stage of relativistic heavy-ion collisions, we investigate, from a phenomenological point of view, the relevance of non-conventional statistical mechanics effects on the rapidity spectra of net proton yield at AGS, SPS and RHIC. We show that the broad rapidity shape measured at RHIC can be very well reproduced in the framework of a non-linear relativistic Fokker-Planck equation which incorporates non-extensive statistics and anomalous diffusion.

We investigate the relation between the binding energy and the Fermi energy and between different expressions for the pressure in cold nuclear matter. For a self-consistent calculation based on a $\Phi$ derivable $T-$matrix approximation with off-shell propagators the thermodynamic relations are well satisfied unlike for a $G-$matrix or a $T-$matrix approach using quasi-particle propagators in the ladder diagrams

Brueckner-Hartree-Fock calculations are performed for nuclear matter with an exact treatment of the Pauli exclusion operator in the Bethe-Goldstone equation. The differences in the calculated binding energy, compared to the angle-average approximation, which is commonly used, are non-negligible. These difference exhibits a specific density dependence, which shifts the calculated saturation point towards smaller densities. This effect is observed for various versions of modern models for the NN interaction.It is one of the very central and very old projects of nuclear structure theory, to evaluate the saturation properties of nuclear matter from a realistic nucleon-nucleon (NN) interaction without any adjustment of a free parameter. The so-called hole-line expansion or Brueckner-Bethe-Goldstone theory has been one of the tools for solving this manybody problem, which has already been used for many years [1][2][3][4]. These early investigations were successful to some extent. The inclusion of NN correlations in the lowest order of the hole-line expansion, the Brueckner-Hartree-Fock (BHF) approach, turned out to be very important. Realistic models of the NN interaction like the Reid soft-core potential [5] yield an energy of nuclear matter around 150 MeV per nucleon if the effects of correlations are ignored in a mean-field or Hartree-Fock calculation. The BHF approach provides a drastic improvement leading to an energy per nucleon of −11 MeV, which was only by 5 MeV off from the empirical value of −16 MeV per nucleon. Attempts have been made to improve the description of the saturation point further by exploring different NN interactions. It turned out, however, that BHF calculations using these various NN interactions yield results for the saturation point, which fall on the so-called Coester band [6]. They either predict too small binding energy at the empirical value for the density, or about the correct energy at a density, which is too large by a factor of two, or results in between. Comparison of BHF with variational calculations furthermore demonstrated that the inclusion of three-hole line contributions seems to be necessary to obtain a reliable estimate for the binding energy of nuclear matter [7,8].During the last years some progress has been made in this field. It has been shown that a continuous choice for the particle spectrum [9,10] (see also discussion below) accounts for the main part of the effects of three-body correlations. The discrepancy between the calculated saturation points of nuclear matter and the empirical one has significantly been reduced by considering relativistic effects within the Dirac-Brueckner-Hartree-Fock (DBHF) approach [11][12][13]. Finally, it should be mentioned that a new generation of realistic NN potentials has been developed [14][15][16], which yield very accurate fits of proton-neutron and proton-proton scattering. These new potentials, which are essentially phase-shift equivalent remove a large part of the discrepancies observed between older models of the NN interac...

An assessment of the magnitude of the rearrangement contribution to the Fermi energy and to the binding energy per particle is carried out in symmetric nuclear matter by extending the G-matrix framework. The restoration of the thermodynamic consistency or, equivalently, the fulfillment of the Hugenholtz-Van Hove theorem, is discussed.