Complete electroweak O(a) corrections to e⁺e^- -> 4 fermions

by Ansgar Denner (PSI)

Friday 2 Dec 2005, 14:00 → 15:00 Europe/Zurich

TH Auditorium (CERN)

The measurement of the W-boson mass with an error of the order of 5 MeV at the ILC requires the calculation of the complete O(α) corrections to W-boson-pair-mediated 4-fermion production. In this talk a calculation of the complete electroweak O(α) corrections for the charged-current four-fermion production processes e⁺ e^- -> n_τ τ⁺ μ^- \bar{ν}_μ , u \bar{d} μ^- \bar{ν}_μ, and u \bar{d} s \bar{c} is described. The new techniques introduced in this calculation include a complex-mass scheme for the consistent implementation of the finite W-boson width in a one-loop calculation. The effects of the O(α) corrections on the total cross sections and various distributions are discussed and compared to predictions based on the double-pole approximation, which were used for the analysis of LEP2 experiments.