Enhanced Deuteron Coalescence Probability in Jets

Scientific paper - Original scientific paper

• Author: Sheryasi Acharya
• Author: ...
• Author: Filip Erhardt
• Author: ...
• Author: Sven Gotovac
• Author: ...
• Author: Marko Jerčić
• Author: ...
• Author: David Karatović
• Author: ...
• Author: Petra Lončar
• Author: ...
• Author: Mirko Planinić
• Author: ...
• Author: Nikola Poljak
• Author: ...
• Author: Linda Vicković
• Author: ...
• Author: Nicola 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)

The transverse-momentum (pT) spectra and coalescence parameters B2 of (anti)deuterons are measured in p-p collisions at √s = 13 TeV for the first time in and out of jets. In this measurement, the direction of the leading particle with the highest pT in the event (p leadT > 5 GeV/c) is used as an approximation for the jet axis. The event is consequently divided into three azimuthal regions, and the jet signal is obtained as the difference between the toward region, that contains jet fragmentation products in addition to the underlying event (UE), and the transverse region, which is dominated by the UE. The coalescence parameter in the jet is found to be approximately a factor of 10 larger than that in the underlying event. This experimental observation is consistent with the coalescence picture and can be attributed to the smaller average phase-space distance between nucleons in the jet cone as compared with the underlying event. The results presented in this Letter are compared to predictions from a simple nucleon coalescence model, where the phase-space distributions of nucleons are generated using pythia8 with the Monash 2013 tuning, and to predictions from a deuteron production model based on ordinary nuclear reactions with parametrized energy-dependent cross sections tuned on data. The latter model is implemented in pythia8.3. Both models reproduce the observed large difference between in-jet and out-of-jet coalescence parameters, although the almost flat trend of the BJet2 is not reproduced by the models, which instead give a decreasing trend.

• Keywords (english): p p: colliding beams; deuteron: production; model: production; model: coalescence; cross section: energy dependence; jet: fragmentation; p p: scattering; nucleon; underlying event; PYTHIA; phase space; GeV; nuclear reaction; transverse momentum: momentum spectrum; transverse momentum; transverse; leading particle; numerical calculations: Monte Carlo; experimental results; 13000 GeV-cms; TeV; CERN LHC Coll; numerical calculations; pi; ALICE
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review Letters
• Numbering: vol. 131, no. 4, 042301
• p-ISSN: 0031-9007
• e-ISSN: 1079-7114
• DOI: https://doi.org/10.1103/PhysRevLett.131.042301
• URN:NBN: urn:nbn:hr:217:451924
• Publication: 2023
• Document URL: https://link.aps.org/doi/10.1103/PhysRevLett.131.042301
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2023 CERN, for the ALICE Collaboration. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Received 26 January 2023; revised 7 April 2023; accepted 5 June 2023; published 26 July 2023.
• Created on: 2024-07-15 13:19:12