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arXiv · 1010.2018

Upper Limits on Electric and Weak Dipole Moments of W-Boson

A. E. Blinov·A. S. Rudenko
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Abstract

The total cross-sections of the reaction e+e- --> W+W-, as measured at LEP-II at centre-of-mass energies between 183 and 207 GeV are used to derive the upper limits on the parameters of CP-violating (P-odd and C-even) triple gauge-boson couplings WWγand WWZ. The 95% CL limits |\widetildeκ_Z|<0.13 and |\widetildeλ_Z|<0.31 are obtained assuming local SU(2)_L x U(1)_Y gauge invariance. Our results are comparable with the previous ones obtained through the analysis of the W decay products. We also discuss the upper limits on the electric dipole moment (EDM) of the W-boson, which follow from the precision measurements of the electron and neutron EDM.

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A. E. Blinov, A. S. Rudenko. 2011-04-11. Upper Limits on Electric and Weak Dipole Moments of W-Boson. https://doi.org/10.1016/j.physletb.2011.04.021

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