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DOE OSTI Β· 3017538

Toward ab-initio nuclear theory calculations of 𝛿 𝐢

Seng, Chien-YeahΒ·Gorchtein, Mikhail
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Abstract

We propose a theory framework to study the isospin-symmetry breaking correction 𝛿 C in superallowed nuclear 𝛽 decays, crucial for the precise determination of |𝑉 𝑒⁒𝑑 |. Based on a general assumptions of the isovector dominance in isospin-symmetry breaking interactions, we construct a set of functions 𝐹 𝑇 𝑧 which involve nuclear matrix elements of isovector monopole operators and the nuclear Green's function. Via the functions 𝐹 𝑇 𝑧 , a connection of 𝛿 C to measurable electroweak nuclear radii is established, providing an experimental gauge of the theory accuracy of 𝛿 C . Here, we outline a strategy to perform ab initio calculations of 𝐹 𝑇 𝑧 based on the Lanczos algorithm, and discuss its similarity with other nuclear-structure-dependent inputs in nuclear 𝛽 decays.

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Ab initio calculationsBeta decayElectroweak interactions in nuclear physicsNuclear charge distributionNuclear many-body theoryNuclear radiiNucleon-nucleon interactionsPhysics

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Seng, Chien-Yeah, Gorchtein, Mikhail. 2024-04-01. Toward ab-initio nuclear theory calculations of 𝛿 𝐢. https://doi.org/10.1103/physrevc.109.044302

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