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arXiv · hep-ph/9605419

Enhanced Supersymmetric Corrections to Top-Quark Production at the Tevatron

J. Kim·J. Lopez·D. Nanopoulos·R. Rangarajan
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Abstract

We calculate the one-loop supersymmetric electroweak-like and QCD-like corrections to the top-quark pair-production cross section at the Tevatron, including the important effects of non-degenerate top-squarks and left-right top-squark mixing. The largest electroweak effects yield a negative shift in the cross section and are enhanced right below the threshold for top-quark decay into top-squark and higgsino-like neutralino, and can be as large as $-35\%$. The largest QCD effects are positive and are enhanced for light top-squark masses, and can be as large as $20\%$. Such shifts greatly exceed the present theoretical uncertainty in the Standard Model prediction, and therefore may be experimentally observable. We also explore the one-loop shifts in scenarios containing light top-squarks and higgsino-like neutralinos that have been recently proposed to explain various apparent experimental anomalies.

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J. Kim, J. Lopez, D. Nanopoulos, R. Rangarajan. 1996-06-07. Enhanced Supersymmetric Corrections to Top-Quark Production at the Tevatron. https://doi.org/10.1103/physrevd.54.4364

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