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Shalom Shlomo

Publications and source records attributed to Shalom Shlomo.

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Simulated-Annealing Optimization of Mean-Field Parameters in a Correlated-Basis Nuclear Model with Realistic Short-Range Correlations

We optimize a six-parameter spherical Woods-Saxon mean field within a first-order correlated-basis-function description of finite nuclei containing central, spin-isospin, and tensor Short-Range Correlations (SRC). Monte Carlo importance sampling makes the multidimensional simulated-annealing search practical. The final objective contains 17 selected charge radii compared with a common theoretical scale of 0.030 fm. This light-to-heavy set is a representative compromise between mass-isospin coverage and the cost of repeatedly evaluating the correlated objective;Two independent fits are performed: S/S, in which the SRC theory uses its own fitted parameters, and 0/0, in which the no-SRC theory uses a separately fitted parameter set. A diagnostic S/0 calculation inserts the no-SRC-fitted parameters into the SRC theory. Its radius metric is 17.49 times the S/S value, demonstrating that the mean field must be refitted when explicit SRC are introduced. After separate optimization, radii, charge densities, and elastic form factors show no universal advantage for either consistent route. The corrected genuinely off-diagonal OBDM retains both uncorrelated kernels and the complete spectator-exchange spin contraction. In momentum space, the correlated S/S and diagnostic S/0 calculations generate the several-percent high-momentum strength observed in 12C and 40Ca, whereas the consistent no-SRC route 0/0 does not. The high-momentum tail is therefore the clearest signature of explicit SRC in the present calculation.

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Improving relativistic energy density functionals with tensor couplings

Energy density functionals (EDFs) have been used extensively with great success to calculate properties of nuclei and to predict the equation of state (EOS) of dense nuclear matter. Besides non-relativistic EDFs, mostly of the Skyrme or Gogny type, relativistic EDFs of different types are in widespread use. In these latter approaches, the effective in-medium interaction is described by an exchange of mesons between nucleons. In most cases, only minimal meson-nucleon couplings are considered. The effects of additional tensor couplings were rarely investigated. In this work, a new relativistic EDF with tensor couplings and density dependent minimal meson-nucleon couplings will be presented. The parameters of the model are determined using a carefully selected set of experimental data with realistic uncertainties that are determined self-consistently. Predictions for various nuclear observables, the nuclear matter equation of state, and properties of neutron stars are discussed.

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