Electroweak non-resonant NLO corrections to e+e- → W+W- b(b)over-bar in the t(t)over-bar resonance region

We analyze subleading electroweak effects in the top anti-top resonance production region in e(+)e(-) collisions which arise due to the decay of the top and anti-top quarks into the W+W- b (b) over bar final state. These are NLO corrections adopting the non-relativistic power counting v similar to alpha(s) similar to root alpha EW. In contrast to the QCD corrections which have been calculated (almost) up to NNNLO, the parametrically larger NLO electroweak contributions have not been completely known so far, but are mandatory for the required accuracy at a future linear collider. The missing parts of these NLO contributions arise from matching coefficients of non-resonant production-decay operators in unstable-particle effective theory which correspond to off-shell top production and decay and other non-resonant irreducible background processes to t (t) over bar production. We consider the total cross section of the e(+)e(-) W+W- b (b) over bar process and additionally implement cuts on the invariant masses of the W(+)b and W-(b) over bar pairs. (C) 2010 Elsevier B.V. All rights reserved.