Non-factorizable photonic corrections to resonant production and decay of many unstable particles

TL;DR

This paper provides explicit analytical formulas for non-factorizable photonic virtual corrections in the production and decay of multiple unstable particles, advancing precise electroweak correction calculations in high-energy physics.

Contribution

It delivers the first explicit analytical results for non-factorizable photonic virtual corrections for any number of unstable particles at one-loop level, aiding next-to-leading-order electroweak computations.

Findings

Explicit analytical results for non-factorizable virtual corrections.

Facilitates precise NLO electroweak calculations in pole approximation.

Results adaptable to non-factorizable QCD corrections.

Abstract

Electroweak radiative corrections to the production of high-multiplicity final states with several intermediate resonances in most cases can be sufficiently well described by the leading contribution of an expansion about the resonance poles. In this approach, also known as pole approximation, corrections are classified into separately gauge-invariant factorizable and non-factorizable corrections, where the former can be attributed to the production and decay of the unstable particles on their mass shell. The remaining non-factorizable corrections are induced by the exchange of soft photons between different production and decay subprocesses. We give explicit analytical results for the non-factorizable photonic virtual corrections to the production of an arbitrary number of unstable particles at the one-loop level and, thus, deliver an essential building block in the calculation of next-to-leading-order electroweak corrections in pole approximation. The remaining virtual factorizable corrections can be obtained with modern automated one-loop matrix-element generators, while the evaluation of the corresponding real photonic corrections can be evaluated with full matrix elements by multi-purpose Monte Carlo generators. Our results can be easily modified to non-factorizable QCD corrections, which are induced by soft-gluon exchange.