The Angular Correlations in Top Quark Decays in Standard Model Extensions

TL;DR

This paper investigates how various Standard Model extensions, including two-Higgs doublet models, top-color assisted technicolor, and noncommutative geometry, can affect angular correlations in top quark decays, impacting measurements at the LHC.

Contribution

It analyzes the influence of several beyond Standard Model theories on the angular correlations in top quark decays, providing insights for experimental searches.

Findings

Spin correlation signatures vary with different models.

Potential deviations from Standard Model predictions identified.

Implications for top quark decay measurements at the LHC.

Abstract

The CMS collaboration at the CERN-LHC have searched for the $t$-channel single top quark production using the spin correlation of the $t$-channel. The signal extraction and cross section measurement relies on the angular distribution of the charged lepton in the top quark decays, the angle between the charged lepton momentum and top spin in the top rest frame. The behavior of the angular distribution is a distinct slope for the t-channel single top (signal) while it is flat for the backgrounds. In this letter we investigate the contributions which this spin correlation may receive from a two-Higgs doublet model, a top-color assisted technicolor (TC2) and the noncommutative extension of the Standard Model.