Precision constraints on the top-quark effective field theory at future lepton colliders

摘要

We examine the constraints that future lepton colliders would impose on theeffective field theory describing modifications of top-quark interactionsbeyond the standard model, through measurements of the $e^+e^-\to bW^+\:\barbW^-$ process. Statistically optimal observables are exploited to constrainsimultaneously and efficiently all relevant operators. Their constraining poweris sufficient for quadratic effective-field-theory contributions to havenegligible impact on limits which are therefore basis independent. This iscontrasted with the measurements of cross sections and forward-backwardasymmetries. An overall measure of constraints strength, the global determinantparameter, is used to determine which run parameters impose the strongestrestriction on the multidimensional effective-field-theory parameter space.