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arXiv · hep-ph/9602305

New Low-energy Leptoquark Interactions

M. Hirsch·H. V. Klapdor-Kleingrothaus·S. G. Kovalenko
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Abstract

We discuss an extension of the standard model (SM) with vector and scalar leptoquarks. The renormalizable leptoquark Lagrangian consistent with the SM gauge symmetry is presented including the leptoquark-Higgs interactions previously not considered in the literature. We discuss the importance of these new interactions for leptoquark phenomenology. After the electro-weak symmetry breaking they generate non-trivial leptoquark mass matrices. These lead to mixing between different $SU(2)_L$-multiplets of the leptoquarks and induce at low energies new effective 4-fermion lepton-quark vertices. The latter affect the standard leptoquark phenomenology. We discuss constraints on these interactions from the helicity-suppressed $π\rightarrow ν+ e$ decay.

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M. Hirsch, H. V. Klapdor-Kleingrothaus, S. G. Kovalenko. 1996-02-14. New Low-energy Leptoquark Interactions. https://doi.org/10.1016/0370-2693(96)00419-4

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