Leading the non-cancelling IR divergences in massless gauge theories: Abelian case

International Workshop on Discovery Physics at the LHC

Khalil, Abdullah^1 ; Horowitz, W.A.^1

Department of Physics, University of Cape Town, Rondebosch

7701, South Africa^1

关键词: Arbitrary number;    Degenerate state;    Divergent series;    Infrared divergences;    Initial state;    Massless electrons;    Monotone convergence theorem;    Next-to-leading order corrections;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/878/1/012022/pdf
DOI  :  10.1088/1742-6596/878/1/012022

来源: IOP

【 摘 要 】

We study the cancellation of both soft and collinear infrared divergences at next-to-leading order correction in a process where a massless electron is scattered off of a static point charge. We show that a self-consistent application of the KLN theorem requires including all initial and final degenerate states, which require including diagrams with an arbitrary number of disconnected photons forming a divergent series. We improve on previous work by rearranging the series in a controlled way and exploit the Monotone Convergence Theorem to prove the uniqueness of our rearranged result. This rearrangement yields a factorization of the infinite contribution from the initial state soft photons, that then cancels in the physically observable cross section.