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arXiv · 1804.04990

Shell-model interactions from chiral effective field theory

Lukas Huth·Victoria Durant·Johannes Simonis·Achim Schwenk
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Abstract

We construct valence-space Hamiltonians for use in shell-model calculations, where the residual two-body interaction is based on symmetry principles and the low-momentum expansion from chiral effective field theory. In addition to the usual free-space contact interactions, we also include novel center-of-mass--dependent operators that arise due to the Galilean invariance breaking by in-medium effects. We fitted the low-energy constants to 441 ground- and excited-state energies in the sd shell and obtained a root-mean-square derivation of 1.8 MeV at leading order and of 0.5 MeV at next-to-leading order, with natural low-energy constants in all cases. The developed chiral shell-model interactions enable order-by-order uncertainty estimates and show promising predictions for neutron-rich isotopes beyond the fitted data set.

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BibTeXRIS

Lukas Huth, Victoria Durant, Johannes Simonis, Achim Schwenk. 2018-11-10. Shell-model interactions from chiral effective field theory. https://doi.org/10.1103/physrevc.98.044301

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