Related papers: Dirac Sea Effects on Superfluidity in Nuclear Matt…
The effects of the Dirac sea of the nucleons are investigated within a covariant model of the hadronic interaction. We extend the usual Mean Field Approximation and present a procedure to deal with divergences which are proportional to…
Effects of the Fermi-sea polarization on the superfluidity in nuclear matter are studied in a framework of quantum hadrodynamics. The particle-hole polarization due to $\sigma$ and $\omega$ mesons enhances the peak value of the pairing gap…
The effect of vacuum fluctuations on the in-medium hadronic properties is investigated using a chiral SU(3) model in the nonlinear realization. The effect of the baryon Dirac sea is seen to modify hadronic properties and in contrast to a…
The ratio $R_T$ of $K^+-^{12}C$ to $K^+-d$ cross sections has been calculated microscopically using a boson-exchange $KN$ amplitude in which the $\sigma$ and $\omega$ mesons are dressed by the modifications of the Dirac sea in nuclear…
We calculate the properties of neutron matter and highlight the physics of chiral three-nucleon forces. For neutrons, only the long-range 2 pi-exchange interactions of the leading chiral three-nucleon forces contribute, and we derive…
Pairing correlations in symmetric nuclear matter are studied within a relativistic mean-field approximation based on a field theory of nucleons coupled to neutral ($\sigma$ and $\omega$) and to charged ($\varrho$) mesons. The Hartree-Fock…
We derive a purely fermionic no-sea effective theory, featuring positive-energy states only for the Walecka model. In contrast to the so-called mean-field theory approach with the no-sea approximation, where the Dirac sea is simply omitted…
The effect nucleon dressing by scattering on the pairing gap in nuclear matter is discussed. Numerical results from self-consistent T-matrix calculations are compared to quasi-particle approximations. The dominant effect of scattering can…
We study the ^{1}S_{0} proton pairing gap in neutron star matter putting emphasis on influence of the Dirac effective mass and the proton fraction on the gap within the relativistic Hartree-Bogoliubov model. The gap equation is solved using…
We study pion propagation in asymmetric nuclear matter (ANM). One of the interesting consequences of pion propagation in ANM is the mode splitting for the different charged states of pions. First we describe the pion-nucleon dynamics using…
In cold atoms and in the crust of neutron stars the pairing gap can reach values comparable with the Fermi energy. While in nuclei the neutron gap is smaller, it is still of the order of a few percent of the Fermi energy. The pairing…
Within the relativistic Hartree approach using a Lagrangian with density-dependent parameters respecting the chiral limit, it is found that the vacuum corrections from the nucleon Dirac sea soften the equation of state and favor the chiral…
The spin symmetry in the Dirac sea has been investigated with relativistic Brueckner-Hartree-Fock theory using the bare nucleon-nucleon interaction. Taking the nucleus $^{16}$O as an example and comparing the theoretical results with the…
We report on recent work concerning the effect which the change in vacuum structure (negative energy Dirac sea), in the presence of a confining scalar field, has on the nucleon structure functions and parton distributions. Using the Dirac…
The explicit energy dependence of the single particle self-energy (dispersive effects), due to short range correlations, is included in the treatment of neutron matter superfluidity. The method can be applied in general to strong…
The induced pairing interaction arising from the exchange of collective surface vibrations among nucleons moving in time reversal states close to the Fermi energy is found to lead to values of the pairing gap which are similar to those…
The superfluidity of neutron matter in the channel $^1 S_0$ is studied by taking into account the effect of the ground-state correlations in the self-energy. To this purpose the gap equation has been solved within the generalized Gorkov…
The Dirac structure of the nucleon self-energy in symmetric nuclear matter as well as neutron matter is derived from a realistic meson exchange model for the nucleon-nucleon (NN) interaction. It is demonstrated that the effects of…
Experiments with cold Fermi atoms can be tuned to probe strongly interacting fluids that are very similar to the low-density neutron matter found in the crusts of neutron stars. In contrast to traditional superfluids and superconductors,…
We review a large body of predictions obtained within the framework of relativistic meson theory together with the Dirac-Brueckner-Hartree-Fock approach to nuclear matter and finite nuclei. The success of this method has been largely…