Anomalous gtt couplings in the Littlest Higgs Model with T-parity

TL;DR

This paper calculates electroweak corrections to the anomalous top-gluon coupling in the Littlest Higgs model with T-parity, revealing how new heavy particles influence top quark pair production at the LHC.

Contribution

It provides the first detailed calculation of electroweak corrections to the $gtar{t}$ coupling in the LHT model, including effects of heavy fermions and Goldstone bosons.

Findings

Electroweak corrections partially cancel in the Standard Model.

New heavy particles contribute positive corrections.

Large invariant mass enhances the heavy particle effects.

Abstract

In this work we calculate the leading electroweak (EW) corrections to the anomalous $gt\bar{t}$ coupling in the Littlest Higgs model with T-parity (LHT), by applying the Goldstone boson equivalence theorem. In the LHT model, such electroweak corrections arise from the loop diagrams of heavy fermions and the ``would-be'' Goldstone bosons. We further examine the EW corrections in the top quark pair production via the quark annihilation process at the LHC. The negative EW corrections in the Standard Model are partially canceled by the positive EW corrections from the loops of the new heavy particles, and the latter dominates in the large invariant mass of the top quark pair.