Radiative Corrections to W^+W^- \to W^+W^- in the Electroweak Standard Model
A. Denner, T. Hahn
TL;DR
The paper addresses radiative corrections to W^+W^- elastic scattering within the electroweak SM. It performs a complete O(α) calculation including virtual and soft-photon contributions for all polarization states, and analyzes the impact on both polarized and unpolarized cross-sections. It tests the Goldstone-boson equivalence theorem at O(α) by comparing purely longitudinal W results from the theorem with direct calculations. It also notes that the intrinsic instability (finite width) of the W boson at one loop prevents a consistent higher-order treatment beyond O(α) for on-shell longitudinal W scattering.
Abstract
The cross-section for W^+W^- \to W^+W^- with arbitrarily polarized W bosons is calculated within the Electroweak Standard Model including the complete virtual and soft-photonic O(alpha) corrections. We show the numerical importance of the radiative corrections for the dominating polarized cross-sections and for the unpolarized cross-section. The numerical accuracy of the equivalence theorem is investigated in O(alpha) by comparing the cross-section for purely longitudinal W bosons obtained from the equivalence theorem and from the direct calculation. We point out that the instability of the W boson, which is inherent in the one-loop corrections, prevents a consistent calculation of radiative corrections to the scattering of on-real-mass-shell longitudinal W bosons beyond O(alpha).