Factorization effect and near-threshold boson production at linear colliders

Summary, in English

We calculate cross-section of the near-threshold three-boson production at the ILC with an account of their instability and a principal part of NLO corrections. The calculations are fulfilled within the framework of the model of unstable particles with smeared mass. We show that the contribution of finite width (instability) is large in the resonance Higgs-mass range and should be taken into account. Suggested approach significantly simplifies calculations with respect to traditional one.