New physics effect on the top-Yukawa coupling at ILC

TL;DR

This paper explores how new physics could significantly alter the top-Yukawa coupling, with measurable effects at the ILC, by analyzing anomalous top-Higgs interactions via specific collider processes.

Contribution

It investigates the impact of dimension-six operators on the top-Yukawa coupling and demonstrates potential large deviations from the Standard Model at the ILC.

Findings

Dimension-six top-Higgs interactions can increase cross sections by hundreds of percent.

Large effects are detectable at the International Linear Collider.

Study provides a method to probe new physics through top quark processes.

Abstract

Measurement of the top-Yukawa coupling is important to understand the fermion mass generation mechanism and dynamics of electroweak symmetry breaking. We discuss the top quark anomalous couplings which can be described by higher dimensional operators. We investigate the process $e^-e^+ \to W^-W^+\nu\bar\nu \to t \bar t \nu\bar\nu$ to study the contribution of the anomalous top-Higgs coupling to the cross section. The effect of the dimension-six top-Higgs interaction on the cross section can be a few hundred percent greater than the SM prediction. Such a large effect can be measured at the International Linear Collider.