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arXiv · 1402.1407

Nonperturbative shell-model interactions from the in-medium similarity renormalization group

S. K. Bogner·H. Hergert·J. D. Holt·A. Schwenk·S. Binder·A. Calci·J. Langhammer·R. Roth
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Abstract

We present the first ab initio construction of valence-space Hamiltonians for medium-mass nuclei based on chiral two- and three-nucleon interactions using the in-medium similarity renormalization group. When applied to the oxygen isotopes, we find experimental ground-state energies are well reproduced, including the flat trend beyond the drip line at 24O. Similarly, natural-parity spectra in 21,22,23,24O are in agreement with experiment, and we present predictions for excited states in 25,26O. The results exhibit a weak dependence on the harmonic-oscillator basis parameter and reproduce spectroscopy within the standard sd valence space.

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S. K. Bogner, H. Hergert, J. D. Holt, A. Schwenk, S. Binder, A. Calci, J. Langhammer, R. Roth. 2014-10-03. Nonperturbative shell-model interactions from the in-medium similarity renormalization group. https://doi.org/10.1103/physrevlett.113.142501

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