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arXiv · 1908.01873

The union of rotational and vibrational modes in generator-coordinate-type calculations, with application to neutrinoless double-beta decay

Abstract

Good many-body methods for medium and heavy nuclei are important. Here we combine ideas from standard generator-coordinate methods (GCM) and the so-called Monte Carlo shell model, and set forth a novel approach: starting from a mean-field solution (Hartree-Fock-Bogoliubov), we create a set of non-orthogonal basis states, by using low-lying vibrational quasiparticleTamm-Dancoff modes, and then project onto states of good angular momentum and particle number. The results we benchmark against full shell model calculations. Even with just a few such modes we find improvement over standard GCM calculations in excitation spectra. We also find significant improvement in $0νββ$ nuclear matrix elements.

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Changfeng Jiao, Calvin W. Johnson. 2019-09-26. The union of rotational and vibrational modes in generator-coordinate-type calculations, with application to neutrinoless double-beta decay. https://doi.org/10.1103/physrevc.100.031303

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