Measurement of the J/ψ polarization with respect to the event plane in Pb–Pb collisions at the LHC
- The polarization of inclusive J/ψ produced in Pb-Pb collisions at sNN−−−√=5.02 TeV at the LHC was studied by ALICE in the dimuon channel, via the measurement of the angular distribution of its decay products. The study was performed in the rapidity region 2.5<y<4, for three transverse momentum intervals (2<pT<4, 4<pT<6, 6<pT<10 GeV/c) and as a function of the centrality of the collision for 2<pT<6 GeV/c. For the first time, the polarization was measured with respect to the event plane of the collision, by considering the angle between the positive-charge decay muon in the J/ψ rest frame and the axis perpendicular to the event-plane vector in the laboratory system. A small transverse polarization is measured, with a significance reaching 3.9σ at low pT and for intermediate centrality values. The polarization could be connected with the existence of a strong magnetic field in the early stage of quark-gluon plasma formation in Pb-Pb collisions, as well as with its behaviour as a rotating fluid with large vorticity.
| URN: | urn:nbn:de:hebis:30:3-801199 |
|---|---|
| URL: | https://arxiv.org/abs/2204.10171v1 |
| DOI: | https://doi.org/10.48550/arXiv.2204.10171 |
| ArXiv Id: | http://arxiv.org/abs/2204.10171v1 |
| Parent Title (German): | arXiv |
| Series (Serial Number): | CERN Report (CERN-EP-2022-066) |
| 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: | 2024/01/05 |
| Issue: | 2204.10171 Version 1 |
| Edition: | Version 1 |
| Page Number: | 10 |
| HeBIS-PPN: | 515065781 |
| 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 |
