Collinear factorisation for e+e- collisions

Stefano Frixione (INFN Genova)

Tuesday, 15 November 2022 at 11:15


Although the computation of a vast class of e+e- cross sections is fully doable in perturbative QED, the perturbative series is not well behaved unless a mechanism is devised that allows one to take into account, to all orders in the coupling constant, the effects due to multiple emissions of photons and e+e- pairs off the incoming particles. I shall discuss one such mechanism, the collinear factorisation approach, that has a strict analogy with its counterpart in QCD and leads to the definition of "Parton" Distribution Functions (PDFs) of the electron and the positron. I shall present recent results that have improved the accuracy to which these PDFs are known, as well as predictions for physical observables at high-energy e+e- colliders.

Slides (PDF, 651 KB)