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Parity Violating Asymmetries in Top Pair Production at Hadron Colliders

Chung Kao·Doreen Wackeroth
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Abstract

We study loop-induced parity violating asymmetries in the strong production of polarized top quark pairs at $pp$ and $p \bar p$ colliders. The electroweak ${\cal O}(α)$ corrections to the helicity amplitudes of $q \bar q \to t \bar t$ and $gg \to t \bar t$ are evaluated in a two Higgs doublet model (2HDM) and the minimal supersymmetric standard model (MSSM). While observables in top quark pair production receive little contribution from standard electroweak interactions, it is possible that they can be significantly enhanced in a 2HDM and the MSSM. We find that the one-loop MSSM electroweak corrections can generate parity violating asymmetries in the total production rate of left- and right-handed top quark pairs up to about 1.7% at the upgraded Tevatron ($\sqrt{S}=2$ TeV) and 3% at the LHC ($\sqrt{S}=14$ TeV).

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Chung Kao, Doreen Wackeroth. 1999-11-01. Parity Violating Asymmetries in Top Pair Production at Hadron Colliders. https://doi.org/10.1103/physrevd.61.055009

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