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Constraints on Extended Neutral Gauge Structures

Jens Erler·Paul Langacker
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Abstract

Indirect precision data are used to constrain the masses of possible extra Z^prime bosons and their mixings with the ordinary Z. We study a variety of Z^prime bosons as they appear in E_6 and left-right unification models, the sequential Z boson, and the example of an additional U(1) in a concrete model from heterotic string theory. In all cases the mixings are severely constrained (sin theta < 0.01). The lower mass limits are generally of the order of several hundred GeV and competitive with collider bounds. The exception is the Z_psi boson, whose vector couplings vanish and whose limits are weaker. The results change little when the rho parameter is allowed, which corresponds to a completely arbitrary Higgs sector. On the other hand, in specific models with minimal Higgs structures the limits are generally pushed into the TeV region.

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Jens Erler, Paul Langacker. 1999-03-24. Constraints on Extended Neutral Gauge Structures. https://doi.org/10.1016/s0370-2693(99)00457-8

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