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arXiv · hep-ph/9403294

Comment on the Dispersion Relations used to Calculate $Δρ$

Tatsu Takeuchi·Aaron K. Grant·Mihir P. Worah
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Abstract

We use the operator product expansion (OPE) to show that non-perturbative QCD corrections to $Δρ$ can be calculated using unsubtracted dispersion relations for either the transverse or the longitudinal vacuum polarization functions. Recent calculations of the non-perturbative contribution to $Δρ$ based on a non-relativistic calculation of corrections to the $\ttbar$ threshold are inconsistent with this result.

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Tatsu Takeuchi, Aaron K. Grant, Mihir P. Worah. 1994-03-15. Comment on the Dispersion Relations used to Calculate $Δρ$. https://doi.org/10.1103/physrevd.51.6457

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