Szczegóły publikacji
Opis bibliograficzny
Polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons along the beam direction in Pb-Pb collisions at $\sqrt{s_{NN}}$=5.02 TeV / S. Acharya, [et al.], B. BALIŚ, [et al.], M. GORGOŃ, [et al.], A. HORZYK, [et al.], M. JABŁOŃSKI, [et al.], J. P. KITOWSKI, [et al.], P. J. KONOPKA, [et al.], S. D. KORYCIAK, [et al.], P. G. RUSSEK, [et al.], // Physical Review Letters ; ISSN 0031-9007 . — 2022 — vol. 128 iss. 17 art. no. 172005, s. 172005-1–172005-13. — Bibliogr. s. 172005-6–172005-7. — Publikacja dostępna online od: 2022-04-29. — P. J. Konopka - dod. afiliacja: European Organization for Nuclear Research (CERN), Geneva, Switzerland
Autorzy (1029)
Dane bibliometryczne
| ID BaDAP | 140342 |
|---|---|
| Data dodania do BaDAP | 2022-06-06 |
| Tekst źródłowy | URL |
| DOI | 10.1103/PhysRevLett.128.172005 |
| Rok publikacji | 2022 |
| Typ publikacji | artykuł w czasopiśmie |
| Otwarty dostęp |  |
| Creative Commons | |
| Czasopismo/seria | Physical Review Letters |
Abstract
The polarization of the Λ and Λ¯ hyperons along the beam (z) direction, Pz, has been measured in Pb-Pb collisions at sNN=5.02 TeV recorded with ALICE at the Large Hadron Collider (LHC). The main contribution to Pz comes from elliptic flow-induced vorticity and can be characterized by the second Fourier sine coefficient Pz,s2=⟨Pzsin(2φ-2Ψ2)⟩, where φ is the hyperon azimuthal emission angle and Ψ2 is the elliptic flow plane angle. We report the measurement of Pz,s2 for different collision centralities and in the 30%–50% centrality interval as a function of the hyperon transverse momentum and rapidity. The Pz,s2 is positive similarly as measured by the STAR Collaboration in Au-Au collisions at sNN=200 GeV, with somewhat smaller amplitude in the semicentral collisions. This is the first experimental evidence of a nonzero hyperon Pz in Pb-Pb collisions at the LHC. The comparison of the measured Pz,s2 with the hydrodynamic model calculations shows sensitivity to the competing contributions from thermal and the recently found shear-induced vorticity, as well as to whether the polarization is acquired at the quark-gluon plasma or the hadronic phase.
