Speaker
Description
In view of the high-precision physics programmes of current and future collider experiments, accurate theoretical predictions for processes involving heavy unstable particles, such as the W and Z bosons or the top quark, are essential. Achieving the required level of precision demands the evaluation of two-loop corrections to the corresponding high-multiplicity and multi-scale amplitudes, whose exact computation remains extremely challenging and is often beyond the reach of current techniques. A powerful framework to address this problem is the Pole Approximation (PA), which exploits the resonant structure of the amplitude and separates higher-order corrections into two gauge-invariant classes: factorisable and non-factorisable contributions. The latter arise from soft gauge-boson exchanges and exhibit a universal structure. In this talk, we present the two-loop electroweak non-factorisable corrections to neutral- and charged-current single-resonance processes and discuss the first steps towards extending the calculation to double-resonance processes.