# PSR21 - Parton Showers and Resummation

25-27 May 2021
Europe/Zurich timezone

## NLP resummation and the endpoint divergent contribution in DIS

Not scheduled
45m
Talk

### Speaker

Leonardo Vernazza (INFN, Torino)

### Description

The off-diagonal parton-scattering channels $g + \gamma^*$ and $q + \phi^*$ in deep-inelastic scattering are power-suppressed near threshold $x\to 1$. In my talk I will discuss the next- to-leading power (NLP) resummation of large double logarithms of $1-x$ to all orders in the strong coupling, which are present even in the off-diagonal DGLAP splitting kernels. The appearance of divergent convolutions prevents the application of factorization methods known from leading power resummation. Employing $d$-dimensional consistency relations from requiring $1/\epsilon$ pole cancellations in dimensional regularization between momentum regions, I will show that the resummation of the off-diagonal parton-scattering channels at the leading logarithmic order can be bootstrapped from the recently conjectured exponentiation of NLP soft-quark Sudakov logarithms. In particular, I will illustrate how the result for the DGLAP kernel in terms of the series of Bernoulli numbers found previously by Vogt can be derived directly from algebraic all-order expressions. I will show that the off-diagonal DGLAP splitting functions and soft-quark Sudakov logarithms can be identified as inherent two-scale quantities in the large-x limit. I will conclude by showing that the conjectured soft-quark Sudakov exponentiation formula can be derived in the context of a refactorization of these scales and renormalization group methods inspired by soft-collinear effective theory.

### Primary authors

Leonardo Vernazza (INFN, Torino) Martin Beneke (Technische Universitaet Muenchen (DE)) Mathias Garny (Technische Universitaet Muenchen (DE)) Sebastian Jaskiewicz (Technical University of Munich) Robert Szafron (Brookhaven National Laboratory) Prof. Jian Wang (Shandong University)

### Presentation materials

There are no materials yet.