Dynamical grooming of QCD jets

TL;DR

This paper introduces a new jet grooming method based on dynamically identifying and removing soft, large-angle branches in QCD jets, leading to IRC and Sudakov safe observables that improve jet analysis.

Contribution

It presents a novel jet grooming technique that dynamically sets phase space cuts using the hardest branch, enhancing the analysis of jet substructure.

Findings

Analytical predictions match Monte Carlo simulations.

The method effectively isolates hard jet components.

Improves understanding of jet mass and momentum sharing distributions.

Abstract

We propose a new class of infrared-collinear (IRC) and Sudakov safe observables with an associated jet grooming technique that removes dynamically soft and large angle branches. It is based on identifying the hardest branch in the Cambridge/Aachen re-clustering sequence and discarding prior splittings that occur at larger angles. This leads to a dynamically generated cut-off on the phase space of the tagged splitting that is encoded in a Sudakov form factor. In this exploratory study we focus on the mass and momentum sharing distributions of the tagged splitting which we analyze analytically to modified leading logarithmic accuracy and compare to Monte-Carlo simulations.