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arXiv · hep-ph/9804366

A Direct Constraint on Dimension-Eight Operators from Z-->neutrino antinetrino gamma

G. Tavares-Velasco·M. A. Perez·M. Maya·B. Vega
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Abstract

We study the radiative decay Z-->neutrino antineutrino gamma whitin an effective Lagrangian approach. Using the search for energetic single-photon events in the data collected by the L3 collaboration, we get direct bounds on the dimension-six and the dimension-eight operators associated with the tau-neutrino magnetic moment and the anomalous electromagnetic properties of the Z boson. As a by-product of our calculation, we reproduce the L3 result for the bound on the tau-neutrino magnetic moment.

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G. Tavares-Velasco, M. A. Perez, M. Maya, B. Vega. 1998-05-18. A Direct Constraint on Dimension-Eight Operators from Z-->neutrino antinetrino gamma. https://doi.org/10.1016/s0370-2693(98)00531-0

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