Global polarization measurement in Au+Au collisions

Abstract

The system created in non central relativistic nucleus-nucleus collisions carries large angular orbital momentum. Due to spin-orbital coupling, produced particles could be globally polarized along the direction of the system angular momentum. We present results of a measurement of Lambda hyperon global polarization in Au+Au collisions at the center of mass energies 62 and 200 GeV with the STAR detector at RHIC. The observed global polarization of Lambda hyperons in the STAR acceptance is consistent with zero within the precision of the measurement. The obtained upper limit, |P_Lambda| < 0.01, is significantly below the theoretical values discussed recently in the literature.

Talk given at SQM 2006, International Conference on Strangeness in Quark Matter, March 26-31, 2006, Los Angeles CA; 4 pages, 2 figures

References in corpus (6)

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• The Cosmological Parameters 2006
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• Spin Alignment of Vector Mesons in Non-central A+A Collisions
• Directed flow in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ =62.4 GeV
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Cited by in corpus (14)

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• Global $\Lambda$ Polarization in high energy collisions
• Quark Polarization in a Viscous Quark-Gluon Plasma
• From Kadanoff--Baym to Boltzmann equations for massive spin-1/2 fermions
• Chiral vortaic effect and neutron asymmetries at NICA
• Heavy quarks in rotating plasma via holography
• Photon polarization as a probe for quark-gluon plasma dynamics
• Fluid Dynamics Study of the $\Lambda$ Polarization for Au+Au Collisions at $\sqrt{s_{NN}}=200$ GeV
• A study of $\Lambda$ and $\bar{\Lambda }$ polarization splitting by meson field in PICR hydrodynamic model
• Global polarization of QGP in non-central heavy ion collisions at high energies
• Effects of finite coverage on global polarization observables in heavy ion collisions
• Centrality dependence of hyperon global polarization in Au+Au collisions at RHIC
• Spin-Vorticity Coupling for Massive Vector Mesons