cancel and have to be determined from matching to the one-loop Standard Model amplitudes for the process $e^+e^-\to\gamma,Z\to t\bar t$. At this order the matching computation can be carried out for an on-shell top-antitop pair at rest. The full set of one-loop electroweak corrections was determined in Ref.[@GuthKuehn]. For the examinations in this work we have to account only for the $bW^+$ and $\bar b W^-$ cuts because, as shown in Sec.\[sectionrenormalization\], only these cuts are relevant for the $bW^+\bar b W^-$ final state that can interfere with top pair production. Because in Ref.[@GuthKuehn] only the sum of all contributions was presented, including the $b\bar b$ and $W^+W^-$ cuts, we rederive the results for the $bW^+$ and $\bar b W^-$ cuts in the next section.

Absorptive Matching Conditions {#sectionmatchingconditions}
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The top pair production diagrams in the full theory that need to be considered to determine the absorptive $bW^+$ and $\bar b W^-$ cuts are shown in Fig.\[figcuts\]. The external (on-shell) top quarks can be taken to be at rest.

![ Full theory diagrams in Feynman gauge that have to be considered to determine the electroweak absorptive parts in the Wilson coefficients $C_A$ and $C_V$ related to the physical $bW^+$ 