Groomed jet mass as a direct probe of collinear parton dynamics

TL;DR

This paper connects the collinear parton dynamics to the groomed jet mass distribution, deriving next-to-leading logarithmic results directly from triple-collinear splitting kernels, offering a fixed-order validation of previous resummation approaches.

Contribution

It provides the first fixed-order derivation of NLL structure from triple-collinear splitting kernels, independently confirming prior SCET-based results.

Findings

Derived NLL structure directly from triple-collinear kernels

Validated previous SCET resummation results

Enhanced understanding of jet mass distribution in QCD

Abstract

We study the link between parton dynamics in the collinear limit and the logarithmically enhanced terms of the groomed jet mass distribution, for jets groomed with the modified mass-drop tagger (mMDT). While the leading-logarithmic (LL) result is linked to collinear evolution with leading-order splitting kernels, here we derive the NLL structure directly from triple-collinear splitting kernels. The calculation we present is a fixed-order calculation in the triple-collinear limit, independent of resummation ingredients and methods. It therefore constitutes a powerful cross-check of the NLL results previously derived using the SCET formalism and provides much of the insight needed for resummation within the traditional QCD approach.