Global polarization of [lambda] hyperons in Au+Au collisions at √sNN=200 GeV

• Verfasst von: Adam, Jaroslav [VerfasserIn]
• Verfasst von: Deppner, Ingo Martin [VerfasserIn]
• Verfasst von: Herrmann, Norbert [VerfasserIn]
• Titel: Global polarization of [lambda] hyperons in Au+Au collisions at √sNN=200 GeV
• Körperschaft: STAR Collaboration [VerfasserIn]
• Verf.angabe: J. Adam, I.M. Deppner, N. Herrmann [und 346 weitere] (STAR Collaboration)
• E-Jahr: 2018
• Jahr: 23 July 2018
• Umfang: 10 S.
• Fussnoten: Im Titel steht der Ausdruck "sNN" unter dem Wurzelsymbol, "NN" ist dabei tiefgestellt ; Im Titel ist "lambda" als griechischer Buchstabe dargestellt ; Gesehen am 05.07.2019
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Woodbury, NY : Inst., 2016
• Jahr Quelle: 2019
• Band/Heft Quelle: 99(2019,1) Artikel-Nummer 014910, 10 Seiten
• ISSN Quelle: 2469-9993
• DOI: doi:10.1103/PhysRevC.98.014910
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1668667053

Abstract

Global polarization of Λ hyperons has been measured to be of the order of a few tenths of a percentage in Au+Au collisions at √sNN = 200 GeV, with no significant difference between Λ and ¯¯¯Λ. These new results reveal the collision energy dependence of the global polarization together with the results previously observed at √sNN = 7.7-62.4 GeV and indicate noticeable vorticity of the medium created in noncentral heavy-ion collisions at the highest Relativistic Heavy Ion Collider collision energy. The signal is in rough quantitative agreement with the theoretical predictions from a hydrodynamic model and from a multi-phase transport model. The polarization is larger in more peripheral collisions, and depends weakly on the hyperon's transverse momentum and pseudorapidity ηH within ∣∣ηH|<1. An indication of the polarization dependence on the event-by-event charge asymmetry is observed at the 2σ level, suggesting a possible contribution to the polarization from the axial current induced by the initial magnetic field.