Scaling of Power Corrections for Angularities from Dressed Gluon Exponentiation

TL;DR

Berger and Magnea analyze power corrections to angularities in e+e- annihilation using Dressed Gluon Exponentiation (DGE). They show that the leading soft-power scaling deduced from Sudakov resummation remains universal when renormalon effects are included, with the scaling tied to boost invariance in the two-jet limit. They also derive a structured pattern for nonleading (collinear) corrections, which are suppressed by non-integer powers of the hard scale and can be modeled via a shape function; these corrections are more model-dependent and smaller for highly negative a. The work provides a framework to predict full angularity distributions across the class from a single nonperturbative shape function, enabling experimental tests of soft radiation universality and the boost-invariance hypothesis in nonperturbative QCD.

Abstract

We study power corrections to a recently introduced family of event shapes, the class of angularities, within the formalism of dressed gluon exponentiation (DGE). We find that the universal scaling rule for the leading power corrections deduced from resummation also holds when taking renormalon enhancements into account. The scaling is due to boost invariance of eikonal dynamics in the two-jet limit, which we recover in the context of DGE. Furthermore, dressed gluon exponentiation provides an ansatz for non-leading power corrections that violate the scaling. These non-leading corrections are further suppressed by non-integer powers of the hard scale.