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arXiv · 1402.1203

On $Z \to γγ$ decay and cancellation of axial anomaly in $Z \to γγ$ transition amplitude for massive fermions

E. V. Zhemchugov
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Abstract

$Z \to γγ$ decay amplitude is considered and proven to be zero due to properties of polarization vectors and Bose statistics. Triangular diagrams for a pseudoscalar $\to γγ$ and $Z \to γγ$ processes with massive fermions in the loop are explicitely calculated. In the Standard Model axial anomaly vanishes in the sum of these diagrams as Z boson is mixed with one of the Goldstone bosons.

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E. V. Zhemchugov. 2014-02-04. On $Z \to γγ$ decay and cancellation of axial anomaly in $Z \to γγ$ transition amplitude for massive fermions. https://doi.org/10.1134/s1063778814100147

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