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Bounds on scalar leptoquark masses from S, T, U parameters in the minimal four-color quark-lepton symmetry model

A. D. Smirnov
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Abstract

The contributions into radiative correction parameters S, T, U from the scalar leptoquarks are calculated in the minimal gauge model with the four-color quark-lepton symmetry. It is shown that the contributions into T and U from the scalar leptoquark doublets are not positive definite. Using the current experimental data on S, T, U the bounds on the scalar leptoquark masses are obtained. In particular, the existence of the relatively light scalar leptoquark with electric charge 2/3 is shown to be compatible with the current experimental data on S, T, U.

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A. D. Smirnov. 1998-05-15. Bounds on scalar leptoquark masses from S, T, U parameters in the minimal four-color quark-lepton symmetry model. https://doi.org/10.1016/s0370-2693(98)00578-4

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