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arXiv · 1901.11106

Ground-state properties of doubly magic nuclei from the unitary-model-operator approach with the chiral two- and three-nucleon forces

T. Miyagi·T. Abe·M. Kohno·P. Navratil·R. Okamoto·T. Otsuka·N. Shimizu·S. R. Stroberg
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Abstract

The ground-state energies and radii for $^{4}$He, $^{16}$O, and $^{40}$Ca are calculated with the unitary-model-operator approach (UMOA). In the present study, we employ the similarity renormalization group (SRG) evolved nucleon-nucleon ($NN$) and three-nucleon ($3N$) interactions based on the chiral effective field theory. This is the first UMOA calculation with both $NN$ and $3N$ interactions. The calculated ground-state energies and radii are consistent with the recent {\it ab initio} results with the same interaction. We evaluate the expectation values with two- and three-body SRG evolved radius operators, in addition to those with the bare radius operator. With the aid of the higher-body evolution of radius operator, it is seen that the calculated radii tend to be SRG resolution-scale independent. We find that the SRG evolution gives minor modifications for the radius operator.

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T. Miyagi, T. Abe, M. Kohno, P. Navratil, R. Okamoto, T. Otsuka, N. Shimizu, S. R. Stroberg. 2019-01-30. Ground-state properties of doubly magic nuclei from the unitary-model-operator approach with the chiral two- and three-nucleon forces. https://doi.org/10.1103/physrevc.100.034310

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