We calculate the Schiff moments of the nuclei 199Hg and 211Ra in completely self-consistent odd-nucleus mean-field theory by modifying the Hartree-Fock-Bogoliubov code HFODD. We allow for arbitrary shape deformation, and include the effects of nucleon dipole moments alongside those of a CP-violating pion-exchange nucleon-nucleon interaction. The results for 199Hg differ significantly from those of previous calculations when the CP-violating interaction is of isovector character.Comment: 7 pages, 2 figure

The density dependencies of various effective interaction strengths in the relativistic mean field are studied and carefully compared for nuclear matter and neutron stars. The influences of different density dependencies are presented and discussed on mean field potentials, saturation properties for nuclear matter, equations of state, maximum masses, and corresponding radii for neutron stars. Though the interaction strengths and the potentials given by various interactions are quite different in nuclear matter, the differences of saturation properties are subtle, except for NL2 and TM2, which are mainly used for light nuclei, while the properties by various interactions for pure neutron matter are quite different. To get an equation of state for neutron matter without any ambiguity, it is necessary to constrain the effective interactions either by microscopic many-body calculations for the neutron matter data or the data of nuclei with extreme isospin. For neutron stars, the interaction with large interaction strengths give strong potentials and large Oppenheimer-Volkoff (OV) mass limits. The density-dependent interactions DD-ME1 and TW-99 favor a large neutron population due to their weak -meson field at high densities. The OV mass limits calculated from different equations of state are 2.02-2.81M ᭪ , and the corresponding radii are 10.78-13.27 km. After the inclusion of the hyperons, the corresponding values become 1.52-2.06M ᭪ and 10.24-11.38 km.

Parity violating electron scattering allows model independent measurements of neutron densities that are free from most strong interaction uncertainties. In this paper we present statistical error estimates for a variety of experiments. The neutron radius Rn can be measured in several nuclei, as long as the nuclear excited states are not too low in energy. We present error estimates for Rn measurements in 40 Ca, 48 Ca, 112 Sn, 120 Sn, 124 Sn, and 208 Pb. In general, we find that the smaller the nucleus, the easier the measurement. This is because smaller nuclei can be measured at higher momentum transfers where the parity violating asymmetry Apv is larger. Also in general, the more neutron rich the isotope, the easier the measurement, because neutron rich isotopes have larger weak charges and larger Apv. Measuring Rn in 48 Ca appears very promising because it has a higher figure of merit than 208 Pb. In addition, Rn( 48 Ca) may be more easily related to two nucleon and three nucleon interactions, including very interesting three neutron forces, than Rn( 208 Pb). After measuring Rn, one can constrain the surface thickness of the neutron density an with a second measurement at somewhat higher momentum transfers. We present statistical error estimates for measuring an in 48 Ca, 120 Sn, and 208 Pb. Again, we find that an is easier to measure in smaller nuclei.

The physical origin of the nuclear symmetry energy is studied within the relativistic mean field (RMF) theory. Based on the nuclear binding energies calculated with and without mean isovector potential for several isobaric chains we confirm earlier Skyrme-Hartree-Fock result that the nuclear symmetry energy strength depends on the mean level spacing ε(A) and an effective mean isovector potential strength κ(A). A detailed analysis of the isospin dependence of the two components contributing to the nuclear symmetry energy reveals a quadratic dependence due to the meanisoscalar potential, ∼ ε T 2 , and, completely unexpectedly, the presence of a strong linear component ∼ κ T (T + 1 + ε/κ) in the isovector potential. The latter generates a nuclear symmetry energy in RMF theory that is proportional to E sym ∼ T (T + 1) at variance to the non-relativistic calculation.The origin of the linear term in RMF theory needs to be further explored.

The recent progress of the relativistic many-body approach by the group at Peking University will be reviewed. In particular, the adiabatic and configuration-fixed constrained triaxial RMF approaches, triaxial RMF approach with time-odd components, a Shell-model-Like APproach (SLAP), a Reflection ASymmetric RMF (RAS-RMF) approach, and a new relativistic Hartree-Fock (RHF) approach with density-dependent σ, ω, ρ and π meson-nucleon couplings for finite nuclei and nuclear matter, will be highlighted.

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