Rising bosonic electroweak virtual effects at high energye+e−colliders

The virtual massive gauge boson effects on several observables in the process of charged fermion pair production at $e^{+}{e}^{-}$ colliders are computed up to the TeV energy range in the standard model, working in the “$Z$-peak-subtracted” representation. It is shown that these effects increase regularly with energy, approaching the typical 10% relative size. A careful numerical evaluation is proposed, where the conditions dictated by gauge invariance are consistently implemented.