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arXiv · 2201.07298

Angular-momentum projection in coupled-cluster theory: structure of $^{34}$Mg

G. Hagen·S. J. Novario·Z. H. Sun·T. Papenbrock·G. R. Jansen·J. G. Lietz·T. Duguet·A. Tichai
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Abstract

Single-reference coupled-cluster theory is an accurate and affordable computational method for the nuclear many-body problem. For open-shell nuclei, the reference state typically breaks rotational invariance and angular momentum must be restored as a good quantum number. We perform angular-momentum projection after variation and employ the disentangled coupled-cluster formalism and a Hermitian approach. We compare our results with benchmarks for $^8$Be and $^{20}$Ne using a two-nucleon interaction from chiral effective field theory and for $pf$-shell nuclei within the traditional shell model. We compute the rotational band in the exotic nucleus $^{34}$Mg and find agreement with data.

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G. Hagen, S. J. Novario, Z. H. Sun, T. Papenbrock, G. R. Jansen, J. G. Lietz, T. Duguet, A. Tichai. 2022-01-18. Angular-momentum projection in coupled-cluster theory: structure of $^{34}$Mg. https://doi.org/10.1103/physrevc.105.064311

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