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Observations Concerning the Magnitude of t \bar{t} Threshold Effects on Electroweak Parameters

Bernd A. Kniehl·Alberto Sirlin
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Abstract

We discuss a recent analysis of $t\bar{t}$ threshold effects and its implications for the determination of electroweak parameters. We show that the new formulation, when applied to the $ρ$ parameter for $m_t\approx158$~GeV, gives a result of similar magnitude to those previously obtained. In fact, it is quite close to our ``resonance'' calculation. We also present a simple estimate of the size of the threshold effects based on an elementary Bohr-atom model of $t\bar{t}$ resonances.

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Bernd A. Kniehl, Alberto Sirlin. 1994-01-12. Observations Concerning the Magnitude of t \bar{t} Threshold Effects on Electroweak Parameters. https://doi.org/10.1103/physrevd.51.3803

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