Centrality dependence of hyperon global polarization in Au+Au collisions at RHIC

Abstract

We present the centrality dependence of Lambda and Anti-Lambda hyperon global polarization in Au+Au collisions at sqrt{s_NN}=62 GeV and 200 GeV measured with the STAR detector at RHIC. Within the precision of the measurement, we observe no centrality dependence of Lambda and Anti-Lambda hyperon global polarization and within our acceptance it is consistent with zero. Different sources of systematic uncertainties (feed down effects, spin precession) are discussed and estimated. The obtained upper limit, |P_{Lambda,Anti-Lambda}| < 0.02, is compared to theoretical predictions discussed recently in literatures.

Talk given at QM 2006, The 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions, November 14-20, 2006, Shanghai, China; 4 pages, 2 figures

References in corpus (6)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• Globally Polarized Quark-gluon Plasma in Non-central A+A Collisions
• Spin Alignment of Vector Mesons in Non-central A+A Collisions
• Global polarization measurement in Au+Au collisions
• Acceptance effects in the hyperons global polarization measurement
• Reconstructing Sigma0 decays in STAR

Cited by in corpus (4)

• Global quark polarization in non-central $A+A$ collisions
• Quark Polarization in a Viscous Quark-Gluon Plasma
• Vector meson's spin alignments in high energy reactions
• Global polarization of QGP in non-central heavy ion collisions at high energies