Polarized baryon production in heavy ion collisions: An analytic hydrodynamical study

Bálint Boldizsár, M. Nagy, M. Csanád

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

In this paper, we utilize known exact analytic solutions of perfect fluid hydrodynamics to analytically calculate the polarization of baryons produced in heavy-ion collisions. Assuming local thermodynamical equilibrium also for spin degrees of freedom, baryons get a net polarization at their formation (freeze-out). This polarization depends on the time evolution of the Quark-Gluon Plasma (QGP), which can be described as an almost perfect fluid. By using exact analytic solutions, we can thus analyze the necessity of rotation (and vorticity) for non-zero net polarization. In this paper, we give the first analytical calculations for the polarization four-vector. We use two hydrodynamical solutions; one is the spherically symmetric Hubble flow (a somewhat oversimplified model, to demonstrate the methodology); and the other solution is a somewhat more involved one that corresponds to a rotating and accelerating expansion, and is thus well-suited for the investigation of some of the main features of the time evolution of the QGP created in peripheral heavy-ion collisions (although there are still numerous features of real collision geometry that are beyond the scope of this simple model). Finally, we illustrate and discuss our results on the polarization.

Original languageEnglish
Article number101
JournalUniverse
Volume5
Issue number5
DOIs
Publication statusPublished - May 1 2019

Fingerprint

ionic collisions
baryons
polarization
quarks
fluids
vorticity
degrees of freedom
hydrodynamics
methodology
collisions
expansion
geometry

Keywords

  • Heavy ion collisions
  • Hydrodynamics
  • Polarization

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Polarized baryon production in heavy ion collisions : An analytic hydrodynamical study. / Boldizsár, Bálint; Nagy, M.; Csanád, M.

In: Universe, Vol. 5, No. 5, 101, 01.05.2019.

Research output: Contribution to journalArticle

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