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arXiv · 2307.14895

New observables for testing Bell inequalities in $W$ boson pair production

Qi Bi·Qing-Hong Cao·Kun Cheng·Hao Zhang
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Abstract

We show that testing Bell inequalities in $W^\pm$ pair systems by measuring their angular correlation suffers from the ambiguity in kinetical reconstruction of the di-lepton decay mode. We further propose a new set of Bell observables based on the measurement of the linear polarization of the $W$ bosons, providing a realistic observable to test Bell inequalities in $W^\pm$ pair systems for the first time.

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Qi Bi, Qing-Hong Cao, Kun Cheng, Hao Zhang. 2023-07-27. New observables for testing Bell inequalities in $W$ boson pair production. https://doi.org/10.1103/physrevd.109.036022

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