CERN Accelerating science

Article
Title Vector meson polarization measurements in pp and Pb--Pb collisions with ALICE at the LHC
Author(s) Bai, Xiaozhi (USTC, Hefei)
Collaboration ALICE Collaboration
Publication 2024
Number of pages 7
In: PoS SPIN2023 (2024) 240
In: 24th International Spin Symposium, Durham, USA, 24 - 29 Sep 2023, pp.240
DOI 10.22323/1.456.0240
Subject category Particle Physics - Experiment ; Nuclear Physics - Experiment
Accelerator/Facility, Experiment CERN LHC ; ALICE
Abstract Polarization measurements are important for understanding the vector mesons production mechanisms in proton proton pp and heavy-ion collisions. Quarkonium measurements in pp collision are crucial to constrain both perturbative and non-perturbative aspects of QCD calculations. The study of quarkonia polarization in pp collisions represents a powerful tool to discriminate among different QCD-based production models. Furthermore, quarkonium polarization measurement in pp collisions can also provide a reference for investigating the fate of charmonium in the quark-gluon plasma (QGP) formed in nucleus-nucleus collisions. When considering heavy-ion collisions, vector meson polarization, as charmed hadrons and quarkonia could, also be used to investigate the characteristics of the QGP. Recently, it has been shown that light vector mesons produced in PbPb collisions are polarized, an effect likely due to the presence of a large angular momentum of the strongly interacting system produced in non-central heavy-ion collisions. It has also been conjectured that vector mesons could be polarized by the strong magnetic field generated in the early phase of the evolution of the system.In this contribution, the recent ALICE measurements of J/psi and Dstar polarization with respect to the reaction plane in PbPb collisions at forward and midrapidity are presented, respectively. The upsilon(1S) polarization with respect to the Collins-Soper and Helicity reference frames in pp collisions at 13 TeV are reported.
Copyright/License publication: © 2024 The authors (License: CC-BY-NC-ND-4.0)

Corresponding record in: Inspire


 Record created 2024-12-22, last modified 2024-12-22


Fulltext:
Download fulltext
PDF