Detecting quark anomalous electroweak couplings at the LHC

TL;DR

This paper analyzes the potential of the LHC and future colliders to detect quark anomalous electroweak couplings using effective Lagrangian methods, focusing on various processes and their sensitivities.

Contribution

It provides a detailed study of constraints on dimension-6 quark anomalous couplings at the LHC and future colliders, including kinematic analysis and sensitivity estimates.

Findings

14 TeV LHC can test couplings of O(0.1-1) TeV^{-2}

Certain processes improve sensitivity to O(0.01-0.1) TeV^{-2}

Future 100 TeV collider enhances detection sensitivity by about ten times

Abstract

We study the dimension-6 quark anomalous electroweak couplings in the formulation of linearly realized effective Lagrangian. We investigate the constraints on these anomalous couplings from the $pp \rightarrow W^+W^-$ process in detail at the LHC. With additional kinematic cuts, we find that the 14 TeV LHC can provide a test of anomalous couplings of $O(0.1-1)\,{\rm TeV}^{-2}$. The $pp \rightarrow ZZ/Z\gamma/\gamma\gamma$ processes can provide a good complement as they are sensitive to those anomalous couplings which do not affect the $pp \rightarrow W^+W^-$ process. Those processes that only contain anomalous triple vertices, like $p p \to W^* \to l \nu_l$ or $p p \to \gamma^* / Z^* \to l^+ l^-$, can improve the sensitivities to $O(0.01-0.1)\,{\rm TeV}^{-2}$. We also study the kinematic differences between different anomalous couplings and discuss the potential of the $\chi^2$-analysis to distinguish them. Finally, we discuss the detection ability of the possible future 100 TeV proton-proton collider(SPPC), and find that the detection sensitivity is improved by about one order of magnitude compared with the LHC.