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arXiv · 0807.3687

Long Range Tensor Correlations in Charge and Parity Projected Fermionic Molecular Dynamics

Sonia Bacca·Hans Feldmeier·Thomas Neff
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Abstract

Within the framework of Fermionic Molecular Dynamics a method is developed to better account for long range tensor correlations in nuclei when working with a single Slater determinant. Single-particle states with mixed isospin and broken parity build up an intrinsic Slater determinant which is then charge and parity projected. By minimizing the energy of this many-body state with respect to the parameters of the single-particle states and projecting afterwards on angular momentum ground state energies are obtained that are systematically lower than corresponding Hartree-Fock results. The realistic Argonne V18 potential is used and short range correlations are treated with the Unitary Correlation Operator Method. Comparison with exact few-body calculations shows that in $^4$He about one fifth of the correlation energy due to long-range correlations are accounted for. These correlations which extend over the whole nucleus are visualized with the isospin and spin-isospin density of the intrinsic state. The divergence of the spin-isospin density, the source for pion fields, turns out to be of dipole nature.

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Sonia Bacca, Hans Feldmeier, Thomas Neff. 2008-07-23. Long Range Tensor Correlations in Charge and Parity Projected Fermionic Molecular Dynamics. https://doi.org/10.1103/physrevc.78.044306

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