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arXiv · 2406.13010

IMSRG with flowing 3 body operators, and approximations thereof

S. R. Stroberg·T. D. Morris·B. C. He
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Abstract

We explore the impact of retaining three-body operators within the in-medium similarity renormalization group (IMSRG), as well as various approximations schemes. After studying two toy problems, idential fermions with a contact interaction and the Lipkin-Meshkov-Glick model, we employ the valence-space formulation of the IMSRG to investigate the even-$A$ carbon isotopes with a chiral two-body potential. We find that retaining only those commutators expressions that scale as $N^7$ provides an excellent approximation of the full three-body treatment.

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S. R. Stroberg, T. D. Morris, B. C. He. 2024-06-18. IMSRG with flowing 3 body operators, and approximations thereof. https://doi.org/10.1103/physrevc.110.044316

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