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arXiv · hep-ph/9707229

$t \to cWW$ and $WW \to \bar{t}c + t\bar{c}$ in Extended Models

David Atwood·Marc Sher
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Abstract

Jenkins has pointed out that the process $t\to cW^+W^-$ is GIM suppressed in the standard model. In this note, we calculate the branching ratio for a wide range of models, in which the decay occurs at tree level through exchange of a scalar, fermion or vector. In the case of scalar exchange, a scalar mass between $2m_W$ and 200 GeV leads to a resonant enhancement, giving a branching ratio as high as a few tenths of a percent. We then note that all of these models will also allow $W^+W^-\to \bar{t}c+t\bar{c}$, and we calculate the single-top/single-charm production rate at the LHC. The rates aren't negligibly small, but the background from single-top/single-bottom production will probably swamp the signal.

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David Atwood, Marc Sher. 1997-07-03. $t \to cWW$ and $WW \to \bar{t}c + t\bar{c}$ in Extended Models. https://doi.org/10.1016/s0370-2693(97)00976-3

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