In-medium similarity renormalization group with chiral two- plus three-nucleon interactions

Abstract

We use the recently proposed in-medium similarity renormalization group (IM-SRG) to carry out a systematic study of closed-shell nuclei up to ${}^{56}\mathrm{Ni}$, based on chiral two- plus three-nucleon interactions. We analyze the capabilities of the IM-SRG by comparing our results for the ground-state energy to coupled cluster calculations, as well as to quasiexact results from the importance-truncated no-core shell model. Using chiral two- plus three-nucleon Hamiltonians whose resolution scales are lowered by free-space SRG evolution, we obtain good agreement with experimental binding energies in ${}^{4}\mathrm{He}$ and the closed-shell oxygen isotopes, while the calcium and nickel isotopes are somewhat overbound.