Leif Lönnblad
Professor
Systematics of quark/gluon tagging
Author
Summary, in English
By measuring the substructure of a jet, one can assign it a “quark” or “gluon” tag. In the eikonal (double-logarithmic) limit, quark/gluon discrimination is determined solely by the color factor of the initiating parton (CF versus CA). In this paper, we confront the challenges faced when going beyond this leading-order understanding, using both parton-shower generators and first-principles calculations to assess the impact of higher-order perturbative and nonperturbative physics. Working in the idealized context of electron-positron collisions, where one can define a proxy for quark and gluon jets based on the Lorentz structure of the production vertex, we find a fascinating interplay between perturbative shower effects and nonperturbative hadronization effects. Turning to proton-proton collisions, we highlight a core set of measurements that would constrain current uncertainties in quark/gluon tagging and improve the overall modeling of jets at the Large Hadron Collider.
Department/s
- Theoretical Particle Physics - Has been reorganised
Publishing year
2017-07-01
Language
English
Publication/Series
Journal of High Energy Physics
Volume
2017
Issue
7
Document type
Journal article
Publisher
Springer
Topic
- Subatomic Physics
Keywords
- Jets
- QCD Phenomenology
Status
Published
Project
- QCD Phenomenology and Event Generator Development
- Innovative Network for Monte Carlo Event Generators for LHC Physics
ISBN/ISSN/Other
- ISSN: 1029-8479