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arXiv · 1806.07405

Shell-model coupled-cluster method for open-shell nuclei

Z. H. Sun·T. D. Morris·G. Hagen·G. R. Jansen·T. Papenbrock
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Abstract

We present an approach to derive effective shell-model interactions from microscopic nuclear forces. The similarity-transformed coupled-cluster Hamiltonian decouples the single-reference state of a closed-shell nucleus and provides us with a core for the shell model. We use a second similarity transformation to decouple a shell-model space from the excluded space. We show that the three-body terms induced by both similarity transformations are crucial for an accurate computation of ground and excited states. As a proof of principle we use a nucleon-nucleon interaction from chiral effective field theory, employ a $^4$He core, and compute low-lying states of $^{6-8}$He and $^{6-8}$Li in $p$-shell model spaces. Our results agree with benchmarks from full configuration interaction.

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Z. H. Sun, T. D. Morris, G. Hagen, G. R. Jansen, T. Papenbrock. 2018-06-19. Shell-model coupled-cluster method for open-shell nuclei. https://doi.org/10.1103/physrevc.98.054320

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