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arXiv · 1104.3122

Effective Field Theory for Nonstandard Top Quark Couplings

Nicolas Greiner·Scott Willenbrock·Cen Zhang
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Abstract

We present an effective-field-theory calculation of the effect of a dimension-six operator involving the top quark on precision electroweak data via a top-quark loop. We demonstrate the renormalizability, in the modern sense, of the effective field theory. We use the oblique parameter U to bound the coefficient of the operator, and compare with the bound derived from top-quark decay.

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Nicolas Greiner, Scott Willenbrock, Cen Zhang. 2011-04-15. Effective Field Theory for Nonstandard Top Quark Couplings. https://doi.org/10.1016/j.physletb.2011.09.026

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