Parity Violating Asymmetries in Top Pair Production at Hadron Colliders

TL;DR

This paper investigates loop-induced parity violating asymmetries in top quark pair production at hadron colliders, showing that beyond Standard Model theories like 2HDM and MSSM can significantly enhance these asymmetries.

Contribution

It provides the first detailed calculation of electroweak corrections to top pair production in 2HDM and MSSM, highlighting potential observable effects.

Findings

MSSM can produce parity asymmetries up to 1.7% at Tevatron

Asymmetries can reach about 3% at LHC energies

Electroweak corrections are negligible in Standard Model but significant in extended models

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 ${\cal O}(\alpha)$ 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).