Measurement of inclusive and leading subjet fragmentation in pp and Pb–Pb collisions at √sNN = 5.02 TeV
- This article presents new measurements of the fragmentation properties of jets in both proton-proton (pp) and heavy-ion collisions with the ALICE experiment at the Large Hadron Collider (LHC). We report distributions of the fraction zr of transverse momentum carried by subjets of radius r within jets of radius R. Charged-particle jets are reconstructed at midrapidity using the anti-kT algorithm with jet radius R=0.4, and subjets are reconstructed by reclustering the jet constituents using the anti-kT algorithm with radii r=0.1 and r=0.2. In proton-proton collisions, we measure both the inclusive and leading subjet distributions. We compare these measurements to perturbative calculations at next-to-leading logarithmic accuracy, which suggest a large impact of threshold resummation and hadronization effects on the zr distribution. In heavy-ion collisions, we measure the leading subjet distributions, which allow access to a region of harder jet fragmentation than has been probed by previous measurements of jet quenching via hadron fragmentation distributions. The zr distributions enable extraction of the parton-to-subjet fragmentation function and allow for tests of the universality of jet fragmentation functions in the quark-gluon plasma (QGP). We find indications that there is a turnover in the ratio between the distributions in Pb-Pb and pp collisions as zr→1, exposing qualitatively new possibilities to disentangle competing jet quenching mechanisms. By comparing our results to theoretical calculations based on an independent extraction of the parton-to-jet fragmentation function, we find consistency with the universality of jet fragmentation and no indication of factorization breaking in the QGP.
| URN: | urn:nbn:de:hebis:30:3-801487 |
|---|---|
| URL: | https://arxiv.org/abs/2204.10270v1 |
| DOI: | https://doi.org/10.48550/arXiv.2204.10270 |
| ArXiv Id: | http://arxiv.org/abs/2204.10270v1 |
| Parent Title (German): | arXiv |
| Series (Serial Number): | CERN Report (CERN-EP-2022-060) |
| Publisher: | arXiv |
| Document Type: | Preprint |
| Language: | English |
| Date of Publication (online): | 2022/04/21 |
| Date of first Publication: | 2022/04/21 |
| Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
| Creating Corporation: | ALICE (Körperschaft) |
| Release Date: | 2024/01/12 |
| Issue: | 2204.10270 Version 1 |
| Edition: | Version 1 |
| Page Number: | 20 |
| HeBIS-PPN: | 515424692 |
| Institutes: | Physik / Physik |
| Informatik und Mathematik / Informatik | |
| Wissenschaftliche Zentren und koordinierte Programme / Frankfurt Institute for Advanced Studies (FIAS) | |
| Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
| Sammlungen: | Universitätspublikationen |
| Licence (German): |  Creative Commons - Namensnennung 4.0 |
