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arXiv · hep-ph/9903391

The decay Z -> neutrino antineutrino photon in the Standard Model

J. M. Hernandez·M. A. Perez·G. Tavares-Velasco·J. J. Toscano
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Abstract

A complete study of the one-loop induced decay Z -> neutrino antineutrino photon is presented within the framework of the Standard Model. The advantages of using a nonlinear gauge are stressed. We have found that the main contributions come from the electric dipole and the magnetic dipole transitions of the Z gauge boson and the neutrino, respectively. We obtain a branching ratio B=7.16E-10, which is about four orders of magnitude smaller than the bound recentely obtained by the L3 collaboration and thus it leaves open a window to search for new physics effects in single-photon decays of the Z boson.

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J. M. Hernandez, M. A. Perez, G. Tavares-Velasco, J. J. Toscano. 1999-03-17. The decay Z -> neutrino antineutrino photon in the Standard Model. https://doi.org/10.1103/physrevd.60.013004

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