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arXiv · hep-ph/9406347

Vector Leptoquarks Could Be Rather Light?

A. V. Kuznetsov·N. V. Mikheev
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Abstract

Some low-energy manifestations of a minimal extension of the Standard Model based on the quark-lepton $SU(4)_V \otimes SU(2)_L \otimes G_R$ symmetry of the Pati-Salam type are analysed. Given this symmetry a new type of mixing in the quark-lepton interactions is shown to be required. An additional arbitrariness of the mixing parameters could allow to decrease noticeably the lower bound on the leptoquark mass $M_X$ originated from the $π$ and $K$ decays and the $μe$ conversion. The only mixing independent bound emerging from the cosmological limit on the $π^0 \rightarrow ν\barν$ decay width is $M_X > 18~TeV$.

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A. V. Kuznetsov, N. V. Mikheev. 1994-06-21. Vector Leptoquarks Could Be Rather Light?. https://doi.org/10.1016/0370-2693(94)90775-7

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