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arXiv · 1006.3639

In-Medium Similarity Renormalization Group for Nuclei

K. Tsukiyama·S. K. Bogner·A. Schwenk
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Abstract

We present a new ab-initio method that uses similarity renormalization group (SRG) techniques to continuously diagonalize nuclear many-body Hamiltonians. In contrast with applications of the SRG to two- and three-nucleon interactions in free space, we perform the SRG evolution "in medium" directly in the $A$-body system of interest. The in-medium approach has the advantage that one can approximately evolve $3,...,A$-body operators using only two-body machinery based on normal-ordering techniques. The method is nonperturbative and can be tailored to problems ranging from the diagonalization of closed-shell nuclei to the construction of effective valence shell-model Hamiltonians and operators. We present first results for the ground-state energies of $^4$He, $^{16}$O and $^{40}$Ca, which have accuracies comparable to coupled-cluster calculations.

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K. Tsukiyama, S. K. Bogner, A. Schwenk. 2011-05-24. In-Medium Similarity Renormalization Group for Nuclei. https://doi.org/10.1103/physrevlett.106.222502

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