Detecting quark anomalous electroweak couplings at the LHC

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.