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arXiv · hep-ph/9610416

The tau forward-backward Asymmetry within Grand Unified Theories

F. Caravaglios
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Abstract

We will study some possible non universal corrections that could affect single measurements of the Weinberg angle sin^2(theta) (leaving the full average essentially unchanged). We will concentrate on the class of the models that introduces a new light gauge boson and an extended Higgs sector, but we restrict the Higgs charges choice in order to automatically achieve zero mixing at the tree level between the Z_0 and the Z'. This will more naturally keep small the universal effects with a relatively light Z', but it will imply only vector-like coupling between this boson and the standard fermions. A SO(10) gauge boson which distinguishes between families can have such properties and could explain a deviation in the tau forward-backward asymmetry without affecting the tau polarization measurements at LEP.

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F. Caravaglios. 1996-10-18. The tau forward-backward Asymmetry within Grand Unified Theories. https://doi.org/10.1016/s0370-2693(97)01696-1

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