Effective Field Theory for Nonstandard Top Quark Couplings

Understand

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.