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arXiv · hep-ph/9409321

Could Vector Leptoquarks be Rather Light?

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

A possible Standard Model extension of the Pati-Salam type with a lepton number as the fourth color is reexamined. A new type of mixing in the interaction of the $SU(4)_V$--leptoquark with quarks and leptons 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. 1994-09-15. Could Vector Leptoquarks be Rather Light?. https://arxiv.org/abs/hep-ph/9409321

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