KLN cancellation of initial-state singularities in Deep Inelastic Scattering

by Zeno Capatti (University of Bern)

Thursday May 9, 2024, 2:00 PM → 3:00 PM Europe/Zurich

(U1-02) (University of Milan-Bicocca)

After introducing the problem of initial-state collinear singularities in Deep Inelastic Scattering, I will demonstrate how these singularities can be cancelled by applying the KLN theorem, which requires the inclusion of new diagrams featuring multi-partonic initial states and spectator states. In particular, I will show how these diagrams naturally arise from Time-Ordered Perturbation Theory and how the cancellation of singularities can be achieved at the integrand level within the Local Unitarity framework. If time permits, I will explore what typical Operator Product Expansion arguments suggest about the influence and factorisation properties of these additional diagrammatic contributions.