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arXiv · 2012.03699

A novel method to test particle ordering and final state alignment in helicity formalism

Mengzhen Wang·Yi Jiang·Yinrui Liu·Wenbin Qian·Xiaorui Lyu·Liming Zhang
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Abstract

In this article, the importance is demonstrated of a proper choice of reference particles for decay angle definitions, when constructing partial-wave amplitude of multi-body decays using helicity formalism. This issue is often ignored in the standard use case of the helicity formalism. A new technique is proposed to determine the correct particle ordering, and can also be used as a generalized method to calculate the rotation operators used for the final-state alignment between different decay chains. Numerical validations are also performed to support the arguments and new technique proposed in this article.

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Mengzhen Wang, Yi Jiang, Yinrui Liu, Wenbin Qian, Xiaorui Lyu, Liming Zhang. 2020-12-07. A novel method to test particle ordering and final state alignment in helicity formalism. https://doi.org/10.1088/1674-1137/abf139

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