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CP-odd WWZ couplings induced by vector-like quarks

Eri Asakawa·Miho Marui·Noriyuki Oshimo·Tomomi Saito·Akio Sugamoto
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Abstract

A minimal extension of the standard model includes extra quarks with charges 2/3 and/or -1/3, whose left-handed and right-handed components are both SU(2) singlets. This model predicts new interactions of flavor-changing neutral current at the tree level, which also violate CP invariance. We study CP-odd anomalous couplings for the gauge bosons W, W, and Z induced by the new interactions at the one-loop level. These couplings become nonnegligible only if both an up-type and a down-type extra quarks are incorporated. Their form factors are estimated to be maximally of order $10^{-5}$. Such magnitudes are larger than those predicted in the standard model, though smaller than those in certain other models.

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Eri Asakawa, Miho Marui, Noriyuki Oshimo, Tomomi Saito, Akio Sugamoto. 1999-03-13. CP-odd WWZ couplings induced by vector-like quarks. https://doi.org/10.1007/s100529900117

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