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The One-Body and Two-Body Density Matrices of Finite Nuclei and Center-of-Mass Correlations

A. Shebeko·P. Papakonstantinou·E. Mavrommatis
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Abstract

A method is presented for the calculation of the one-body and two-body density matrices and their Fourier transforms in momentum space, that is consistent with the requirement for translational invariance, in the case of a nucleus (a finite self-bound system). We restore translational invariance by using the so-called fixed center-of-mass approximation for constructing an intrinsic nuclear ground state wavefunction by starting from a non-translationally invariant wavefunction and applying a projection prescription. We discuss results for the one-body and two-body momentum distributions of the 4He nucleus calculated with the Slater determinant of the harmonic oscillator orbitals, as the initial non-translationally invariant wavefunction. Effects of such an inclusion of CM correlations are found to be quite important in the momentum distributions.

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A. Shebeko, P. Papakonstantinou, E. Mavrommatis. 2005-12-14. The One-Body and Two-Body Density Matrices of Finite Nuclei and Center-of-Mass Correlations. https://doi.org/10.1063/1.2200903

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