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arXiv · 2205.12975

The Mathematical Structure of $U$-Spin Amplitude Sum Rules

Margarita Gavrilova·Yuval Grossman·Stefan Schacht
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Abstract

We perform a systematic study of $SU(2)$ flavor amplitude sum rules with particular emphasis on $U$-spin. This study reveals a rich mathematical structure underlying the sum rules that allows us to formulate an algorithm for deriving all $U$-spin amplitude sum rules to any order of the symmetry breaking. This novel approach to deriving the sum rules does not require one to explicitly compute the Clebsch-Gordan tables, and allows for simple diagrammatic interpretation. Several examples that demonstrate the application of our novel method to systems that can be probed experimentally are provided.

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Margarita Gavrilova, Yuval Grossman, Stefan Schacht. 2022-05-25. The Mathematical Structure of $U$-Spin Amplitude Sum Rules. https://doi.org/10.1007/jhep08(2022)278

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