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arXiv:1808.00518

Exploring density-dependent effective interactions with quantum Monte Carlo

P. Massella, F. Barranco, Diego Lonardoni, Alessandro Lovato, Francesco Pederiva, E. Vigezzi

Published Aug 1, 2018• 0 citations
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Abstract

We investigate some aspects of the connection between mean-field and ab-initio calculations for many-nucleon systems employing the Gogny effective interaction. In particular, we present variational Monte Carlo calculations of $^4$He and $^{16}$O, for which we extended the formalism of the linear method to the case of a density-dependent Hamiltonian. Monte Carlo calculations using an uncorrelated basis reduce to Hartree-Fock ones, but Galilean invariance can be preserved, contrary to the usual treatment. An analysis of the results obtained with the Gogny force when used in conjunction with correlated wave functions has also been performed. Calculations show the collapse of the deuteron, leading to a set of unphysical predictions for the structure of heavier nuclei. This behavior remarks the different role of the Gogny effective interaction as compared to bare interactions typically used in fully microscopic calculations.

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