Global spin polarization of multistrange hyperons and feed-down effect in heavy-ion collisions

Abstract

Global spin polarization of hyperons is an important observable to probe the vorticity of the quark-gluon plasma produced in heavy-ion collisions. We calculate the global polarizations of $\Lambda$, ${\Xi }^{-}$, and ${\Omega }^{-}$ in Au+Au collisions at energies $\sqrt{s_{\text{NN}}}=$ 7.7--200 GeV based on a multiphase transport model. Our calculations suggest that their primary global polarizations fulfill $P_{{\Omega }^{-}}\simeq 5/3P_{{\Xi }^{-}}\simeq 5/3P_{\Lambda }$. We also estimate the feed-down effect of particle decay on the global polarization. With the feed-down effect taken into account, the global polarizations of $\Lambda$ and ${\Xi }^{-}$ are clearly separated, and the final global polarizations are in the ordering: $P_{{\Omega }^{-}}>P_{{\Xi }^{-}}>P_{\Lambda }$. Such a relation can be tested in experiments, which will provide us more information about the global polarization mechanism.

6 pages, 3 figures. v2: discussion added

References in corpus (16)

• Angular momentum conservation in heavy ion collisions at very high energy
• Global quark polarization in non-central $A+A$ collisions
• Shear-induced spin polarization in heavy-ion collisions
• Fate of spin polarization in a relativistic fluid: An entropy-current analysis
• Local polarization and isothermal local equilibrium in relativistic heavy ion collisions
• Spin-thermal shear coupling in a relativistic fluid
• Global $\Lambda$ Polarization in high energy collisions
• Spin polarization induced by the hydrodynamic gradients
• Evolution of transverse flow and effective temperatures in the parton phase from a multi-phase transport model
• Global polarization of $\Xi$ and $\Omega$ hyperons in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ = 200 GeV
• Reexamination of local spin polarization beyond global equilibrium in relativistic heavy ion collisions
• A hydrodynamic study of hyperon spin polarization in relativistic heavy ion collisions
• Different space-time freeze-out picture -- an explanation of different $\Lambda$ and $\bar{\Lambda }$ polarization?
• Polarized secondary particles in unpolarized high energy hadron-hadron collisions?
• Spin Polarization Formula for Dirac Fermions at Local Equilibrium
• Damping and polarization rates in near equilibrium state

Cited by in corpus (15)

• Relativistic Spin Magnetohydrodynamics
• Quantum kinetic theory for dynamical spin polarization from QED-type interaction
• Polarization phenomenon in heavy-ion collisions
• Spin Polarization Formula for Dirac Fermions at Local Equilibrium
• Relativistic hydrodynamics with spin in the presence of electromagnetic fields
• Spin evolution of massive fermion in QED plasma
• An introduction to relativistic spin hydrodynamics
• Directed flow and global polarization in Au+Au collisions across energies covered by the beam energy scan at RHIC
• Effect of Coriolis Force on Electrical Conductivity Tensor for Rotating Hadron Resonance Gas
• Effect of the Coriolis force on the electrical conductivity of quark matter: A nonrelativistic description
• Effect of Coriolis force on the shear viscosity of quark matter: A nonrelativistic description
• Event-by-event correlations between $\Lambda$ ($\bar{\Lambda }$) hyperon global polarization and handedness with charged hadron azimuthal separation in Au+Au collisions at $\sqrt{s_{\text{NN}}}=27\text{ GeV}$ from STAR
• Hyperon global polarization in heavy-ion collisions at NICA energies. Feed-down effects and the role of ${\Sigma }^0$ hyperons
• Theoretical aspects of relativistic spin hydrodynamics coupled with electromagnetic fields
• Global hyperon polarization and effects of decay feeddown