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S, T, U parameters in $SU(3)_C\times SU(3)_L\times U(1)$ model with right-handed neutrinos

Hoang Ngoc Long·Takeo Inami
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Abstract

The S, T, U parameters in the $ SU(3)_C\times SU(3)_L\times U(1)$ model with right -handed neutrinos are calculated. Explicit expressions for the oblique and Z - Z' mixing contributions are obtained. We show that the bilepton oblique contributions to S and T parameters are bounded : $- 0.085 \stackrel{<}{\sim} S \stackrel{<}{\sim} 0.05$ and $- 0.001 \stackrel{<}{\sim} T \stackrel{<}{\sim} 0.08$. The Z - Z' mixing contribution is positive and above 10%, but it will increase fastly with the higher Z' mass. %can be negative. The consequent mass splitting of the bilepton is derived and to be 15%. The limit on the mass of the neutral bilepton in this model is obtained.

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Hoang Ngoc Long, Takeo Inami. 1999-02-26. S, T, U parameters in $SU(3)_C\times SU(3)_L\times U(1)$ model with right-handed neutrinos. https://doi.org/10.1103/physrevd.61.075002

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