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arXiv · 2402.18723

Spectroscopy of N=50 isotones with the valence-space density matrix renormalization group

A. Tichai·K. Kapás·T. Miyagi·M. A. Werner·Ö. Legeza·A. Schwenk·G. Zarand
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Abstract

The recently proposed combination of the valence-space in-medium similarity renormalization group (VS-IMSRG) with the density matrix renormalization group (DMRG) offers a scalable and flexible many-body approach for strongly correlated open-shell nuclei. We use the VS-DMRG to investigate the low-lying spectroscopy of N=50 isotones, which are characteristic for their transition between single-particle and collective excitations. We also study electromagnetic transitions and show the advantage of the VS-DMRG to capture the underlying physics more efficiently, with significantly improved convergence compared to state-of-the-art shell-model truncations. Combined with an analysis of quantum information measures, this further establishes the VS-DMRG as a valuable method for ab initio calculations of nuclei.

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A. Tichai, K. Kapás, T. Miyagi, M. A. Werner, Ö. Legeza, A. Schwenk, G. Zarand. 2024-02-28. Spectroscopy of N=50 isotones with the valence-space density matrix renormalization group. https://doi.org/10.1016/j.physletb.2024.138841

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