Analysis of top-quark charged-current coupling at the LHeC

Abstract

In the context of dimension-six operators we study the potential of the Large Hadron Electron Collider (LHeC) to provide information on top-quark effective interactions. We focus on single-antitop production and how it is affected not only by effective coupling but also by four-fermion operators. Compared to the LHC, the LHeC provides a cleaner environment for performing precise measurements of the top-quark production cross section. Therefore, this machine would provide a much better assessment of in the context of the standard model or in the context of higher dimension operators. The LHeC could also provide a slightly better measurement for . For the precise high luminosity phase LHC measurements of and (the W-boson helicity decay ratios of the top quark) would yield better constraints than those obtained by the LHeC. Lepton–quark contact interactions would also be significantly better probed by the LHeC, since the only way of measuring them at the LHC would be through leptonic top decay which is barely sensitive to these interactions.