Global Lambda-hyperon polarization in Au plus Au collisions at root s(NN)=3 GeV

0551858 - ÚJF 2022 RIV US eng J - Journal Article
Abdallah, M. S. - Aboona, B. E. - Adam, J. - Adamczyk, L. - Adams, J. R. - Adkins, J. K. - Bielčík, J. - Bielčíková, Jana - Federič, Pavol - Holub, L. - Chaloupka, P. - Kosarzewski, L. K. - Kramárik, L. - Líčeník, Robert - Ponimatkin, Georgij - Prozorova, V. - Robotková, Monika - Rusňák, Jan - Šimko, Miroslav - Šumbera, Michal - Truhlář, T. - Trzeciak, B. A. - Vaněk, Jan … Total 395 authors
Global Lambda-hyperon polarization in Au plus Au collisions at root s(NN)=3 GeV.
Physical Review C. Roč. 104, č. 6 (2021), č. článku L061901. ISSN 2469-9985. E-ISSN 2469-9993
R&D Projects: GA MŠMT LTT18002
Research Infrastructure: BNL-CZ II - 90109
Institutional support: RVO:61389005
Keywords : STAR collaboration * hyperon polarization
OECD category: Nuclear physics
Impact factor: 3.199, year: 2021
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevC.104.L061901

Global hyperon polarization, (P) over barH, in Au + Au collisions over a large range of collision energy, root S-NN, was recently measured and successfully reproduced by hydrodynamic and transport models with intense fluid vorticity of the quark-gluon plasma. While naive extrapolation of data trends suggests a large (P) over barH as the collision energy is reduced, the behavior of (P) over barH at small root S-NN < 7.7 GeV is unknown. Operating the STAR experiment in fixed-target mode, we measured the polarization of Lambda hyperons along the direction of global angular momentum in Au + Au collisions at root S-NN = 3 GeV. The observation of substantial polarization of 4.91 +/- 0.81(stat.) +/- 0.15(syst.)% in these collisions may require a reexamination of the viscosity of any fluid created in the collision, of the thermalization timescale of rotational modes, and of hadronic mechanisms to produce global polarization.
Permanent Link: http://hdl.handle.net/11104/0327065