Systematics of quark/gluon tagging
| Autor: | Gras, Philippe, Höche, Stefan, Kar, Deepak, Larkoski, Andrew, Lönnblad, Leif, Plätzer, Simon, Siódmok, Andrzej, Skands, Peter, Soyez, Gregory, Thaler, Jesse |
|---|---|
| Rok vydání: | 2017 |
| Předmět: | |
| Zdroj: | JHEP 1707 (2017) 091 |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1007/JHEP07(2017)091 |
| Popis: | 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 (C_F versus C_A). 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. Comment: 50 pages, 20 figures, extended version of the Les Houches 2015 study from arXiv:1605.04692; v2: updated to approximately match journal version, including improved discussion of nonperturbative Casimir scaling and more umlauts |
| Databáze: | arXiv |
| Externí odkaz: |
|