Jet fragmentation transverse momentum distributions in pp and p-Pb collisions at √𝑠, √𝑠NN = 5.02 TeV

Scientific paper - Original scientific paper

• Author: S. Acharya
• Author: ...
• Author: Tome Antičić
• Author: ...
• Author: Filip Erhardt
• Author: ...
• Author: Sven Gotovac
• Author: ...
• Author: Marko Jerčić
• Author: ...
• Author: David Karatović
• Author: ...
• Author: Petra Lončar
• Author: ...
• Author: Eugen Mudnić
• Author: ...
• Author: Mirko Planinić
• Author: ...
• Author: Nikola Poljak
• Author: ...
• Author: Goran Simatović
• Author: ...
• Author: Linda Vicković
• Author: ...
• Author: N. Zurlo
• Collaboration: ALICE Collaboration
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

Jet fragmentation transverse momentum (jT) distributions are measured in proton-proton (pp) and proton-lead (p-Pb) collisions at √𝑠NN = 5.02 TeV with the ALICE experiment at the LHC. Jets are reconstructed with the ALICE tracking detectors and electromagnetic calorimeter using the anti-kT algorithm with resolution parameter R = 0.4 in the pseudorapidity range |η| < 0.25. The jT values are calculated for charged particles inside a fixed cone with a radius R = 0.4 around the reconstructed jet axis. The measured jT distributions are compared with a variety of parton-shower models. Herwig and PYTHIA 8 based models describe the data well for the higher jT region, while they underestimate the lower jT region. The jT distributions are further characterised by fitting them with a function composed of an inverse gamma function for higher jT values (called the “wide component”), related to the perturbative component of the fragmentation process, and with a Gaussian for lower jT values (called the “narrow component”), predominantly connected to the hadronisation process. The width of the Gaussian has only a weak dependence on jet transverse momentum, while that of the inverse gamma function increases with increasing jet transverse momentum. For the narrow component, the measured trends are successfully described by all models except for Herwig. For the wide component, Herwig and PYTHIA 8 based models slightly underestimate the data for the higher jet transverse momentum region. These measurements set constraints on models of jet fragmentation and hadronisation.

• Keywords (english): Heavy Ion Experiments; jet: fragmentation; model: jet; jet: transverse momentum: high; transverse momentum: momentum spectrum; calorimeter: electromagnetic; HERWIG; hadronization; PYTHIA; ALICE; tracking detector; charged particle; CERN LHC Coll; resolution; experimental results; 5020 GeV-cms/nucleon
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Journal of High Energy Physics
• Numbering: vol. 2021, no. 9, 211
• e-ISSN: 1029-8479
• DOI: https://doi.org/10.1007/JHEP09(2021)211
• URN:NBN: urn:nbn:hr:217:455406
• Publication: 2021-09-30
• Document URL: https://link.springer.com/10.1007/JHEP09(2021)211
• Type of resource: Text
• Access conditions: Open access
• Public note: Copyright CERN, for the benefit of the ALICE Collaboration. Article funded by SCOAP3. This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited. Received: December 3, 2020. Revised: August 20, 2021. Accepted: August 31, 2021. Published: September 30, 2021.
• Created on: 2024-09-22 21:09:32