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arXiv · 2412.10693

Spurious Isospin Breaking in the In-medium Similarity Renormalization Group

A. Farren·S. R. Stroberg
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Abstract

Robustly quantifying the uncertainty in the isospin-related theoretical correction $\delta_C$ to superallowed beta decay rates is vital for a correct assessment of CKM unitarity. To this end, we identify the sources of artificial or \textit{spurious} isospin symmetry breaking introduced by the IMSRG many-body framework at a computational level and provide remedies. We test our best policy for preventing spurious ISB by evaluating $\delta_C$.

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A. Farren, S. R. Stroberg. 2024-12-14. Spurious Isospin Breaking in the In-medium Similarity Renormalization Group. https://arxiv.org/abs/2412.10693

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