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arXiv · hep-ph/9707486

Third-generation leptoquark decays and collider searches

M. A. Doncheski·R. W. Robinett
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Abstract

Collider searches for first-, second-, and third-generation scalar (S) or vector (V) leptoquarks (LQs) focus on the quark-lepton decay modes S,V -> q l. For SU(2)-doublet and -triplet leptoquarks with a sufficiently large splitting between the components, decays involving real W-boson emission (such as S_2^{(+5/3)} -> S_2^{(+2/3)} W^{+} and others) become possible and can change the patterns of leptoquark decays. For third-generation leptoquarks, where these mass splittings might be large, such modes could dominate certain leptoquark decays as they are (if kinematically allowed) guaranteed to be of order g^2 where g is the electroweak coupling. We calculate the decay rates for all such processes involving SU(2)-doublet and triplet, scalar and vector leptoquarks. Standard limits on mass splittings from precision electroweak measurements imply that only such decays involving SU(2)-doublet scalar LQs are likely kinematically possible.

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M. A. Doncheski, R. W. Robinett. 1997-07-27. Third-generation leptoquark decays and collider searches. https://doi.org/10.1016/s0370-2693(97)01015-0

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