Global polarization measurement in Au+Au collisions

Abstract

The system created in non-central relativistic nucleus-nucleus collisions possesses large orbital angular momentum. Due to spin-orbit coupling, particles produced in such a system could become globally polarized along the direction of the system angular momentum. We present the results of Lambda and anti-Lambda hyperon global polarization measurements in Au+Au collisions at sqrt{s_NN}=62.4 GeV and 200 GeV performed with the STAR detector at RHIC. The observed global polarization of Lambda and anti-Lambda hyperons in the STAR acceptance is consistent with zero within the precision of the measurements. The obtained upper limit, |P_{Lambda,anti-Lambda}| <= 0.02, is compared to the theoretical values discussed recently in the literature.

11 pages, 10 figures, 1 table, minor changes, accepted for publication in Phys. Rev. C

References in corpus (18)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• Methods for analyzing anisotropic flow in relativistic nuclear collisions
• Flow Study in Relativistic Nuclear Collisions by Fourier Expansion of Azimuthal Particle Distributions
• The STAR Time Projection Chamber: A Unique Tool for Studying High Multiplicity Events at RHIC
• Azimuthal anisotropy in Au+Au collisions at sqrtsNN = 200 GeV
• Globally Polarized Quark-gluon Plasma in Non-central A+A Collisions
• Directed and elliptic flow of charged pions and protons in Pb+Pb collisions at 40 and 158A GeV
• Thermal hadron production in pp and p{\bar p} collisions
• Spin Alignment of Vector Mesons in Non-central A+A Collisions
• The RHIC Zero Degree Calorimeter
• Energy and Charged Particle Flow in 10.8 A GeV/c Au+Au Collisions
• Azimuthal anisotropy of K0s and Lambda prduction at mid-rapidity from Au+Au collisions at root s = 130 GeV
• The Forward Time Projection Chamber (FTPC) in STAR
• Directed flow in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ =62.4 GeV
• Effects of momentum conservation on the analysis of anisotropic flow
• Multiplicity and Pseudorapidity Distributions of Photons in Au + Au Collisions at $\sqrt{s_{NN}}$ = 62.4 GeV
• Acceptance effects in the hyperons global polarization measurement
• Reconstructing Sigma0 decays in STAR

Cited by in corpus (101)

• Global $\Lambda$ hyperon polarization in nuclear collisions: evidence for the most vortical fluid
• Angular momentum conservation in heavy ion collisions at very high energy
• Global polarization of $\Lambda$ hyperons in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ = 200 GeV
• Observation of charge-dependent azimuthal correlations and possible local strong parity violation in heavy ion collisions
• Global hyperon polarization at local thermodynamic equilibrium with vorticity, magnetic field and feed-down
• Study of Lambda polarization in relativistic nuclear collisions at sqrt{s}_NN = 7.7-200 GeV
• Polarization probes of vorticity in heavy ion collisions
• Collective longitudinal polarization in relativistic heavy-ion collisions at very high energy
• Global $\Lambda$ polarization in heavy-ion collisions from a transport model
• Global quark polarization in non-central $A+A$ collisions
• Vortical fluid and $\Lambda$ spin correlations in high-energy heavy-ion collisions
• Lambda Polarization in Peripheral Heavy Ion Collisions
• Polarization of massive fermions in a vortical fluid
• Thermal vorticity and spin polarization in heavy-ion collisions
• Global $\Lambda$ Polarization in high energy collisions
• Lambda hyperon polarization in relativistic heavy ion collisions from the chiral kinetic approach
• Properties of the QCD Matter -- An Experimental Review of Selected Results from RHIC BES Program
• Spin Hydrodynamics and Symmetric Energy-Momentum Tensors -- A current induced by the spin vorticity --
• Global polarization of $\Lambda$ and $\overline{\Lambda }$ hyperons in Pb-Pb collisions at the LHC
• Spin-dependent distribution functions for relativistic hydrodynamics of spin-1/2 particles
• Quark Polarization in a Viscous Quark-Gluon Plasma
• Global polarization of $\Xi$ and $\Omega$ hyperons in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ = 200 GeV
• Thermodynamic versus kinetic approach to polarization-vorticity coupling
• From Kadanoff--Baym to Boltzmann equations for massive spin-1/2 fermions
• A hydrodynamic study of hyperon spin polarization in relativistic heavy ion collisions
• Spin polarization evolution in a boost invariant hydrodynamical background
• Global and local polarization of $\Lambda$ hyperons in Au+Au collisions at 200 GeV from STAR
• A quark coalescence model for polarized vector mesons and baryons
• Vorticity in low-energy heavy-ion collisions
• The Present and Future of QCD
• Global and local spin polarization in heavy ion collisions: a brief overview
• $\Lambda$ and $\bar{\Lambda }$ spin interaction with meson fields generated by the baryon current in high energy nuclear collisions
• Different space-time freeze-out picture -- an explanation of different $\Lambda$ and $\bar{\Lambda }$ polarization?
• Spin polarization dynamics in the Gubser-expanding background
• Spin alignment measurements of the $K^{\ast 0}(892)$ and $\varphi (1020)$ vector mesons at RHIC
• Measurement of global polarization of Λ hyperons in few-GeV heavy-ion collisions
• Vorticity and particle polarization in heavy ion collisions (experimental perspective)
• Relaxation Time for Strange Quark Spin in Rotating Quark-Gluon Plasma
• $\Lambda$ polarization in peripheral collisions at moderate relativistic energies
• Axial anomaly and energy dependence of hyperon polarization in Heavy-Ion Collisions
• Vorticity and Spin Polarization in Heavy Ion Collisions: Transport Models
• Global polarization of $\Lambda$ and $\bar{\Lambda }$ hyperons in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=19.6$ and $27$ GeV
• Heavy quarks in rotating plasma via holography
• Is Hyperon Polarization in Relativistic Heavy Ion Collisions Connected to Axial U(1) Symmetry Breaking at High Temperature?
• Relaxation time for quark spin and thermal vorticity alignment in heavy-ion collisions
• Analytic solutions of relativistic dissipative spin hydrodynamics with radial expansion in Gubser flow
• Off-equilibrium infrared structure of self-interacting scalar fields: Universal scaling, Vortex-antivortex superfluid dynamics and Bose-Einstein condensation
• Investigating different $\Lambda$ and $\bar{\Lambda }$ polarizations in relativistic heavy-ion collisions
• Fluid Dynamics Study of the $\Lambda$ Polarization for Au+Au Collisions at $\sqrt{s_{NN}}=200$ GeV
• Relaxation time for the alignment between the spin of a finite-mass quark/antiquark and the thermal vorticity in relativistic heavy-ion collisions
• Practical considerations for measuring global spin alignment of vector mesons in relativistic heavy ion collisions
• Vector meson's spin alignments in high energy reactions
• Vorticity and Particle Polarization in Relativistic Heavy-Ion Collisions
• A study of $\Lambda$ and $\bar{\Lambda }$ polarization splitting by meson field in PICR hydrodynamic model
• Ultra-relativistic nuclear collisions: where the spectators flow?
• Lambda and Antilambda polarization in Au-Au collisions at RHIC
• Probing the holographic model of $\mathcal{N}=4$ SYM rotating quark-gluon plasma
• Spin versus Helicity Equilibration Times and Lagrangian for Strange Quarks in Rotating Quark-Gluon Plasma
• New mixed inhomogeneous phase in vortical gluon plasma: first-principle results from rotating SU(3) lattice gauge theory
• Effects of finite coverage on global polarization observables in heavy ion collisions
• Effect of magnetic fields on pairs of oppositely charged particles in ultrarelativistic heavy-ion collisions
• Negative Barnett effect, negative moment of inertia of gluon plasma and thermal evaporation of chromomagnetic condensate
• Eddy magnetization from the chiral Barnett effect
• Measurements of spin alignment of vector mesons and global polarization of hyperons with ALICE at the LHC
• Fermion propagator in a rotating environment
• Highlights from STAR heavy ion program
• Nucleon spin polarization in intermediate-energy heavy-ion collisions
• Polarization of Lambda^0 hyperons in nucleus-nucleus collisions at high energies
• Charge asymmetry dependence of the elliptic flow splitting in relativistic heavy-ion collisions
• Inhibition of splitting of the chiral and deconfinement transition due to rotation in QCD: the phase diagram of linear sigma model coupled to Polyakov loop
• Propagation of field disturbances in the Yang-Mills theory
• Heavy quark potential and jet quenching parameter in a rotating D-instanton background
• Signatures of the vortical quark-gluon plasma in hadron yields
• Spin alignment measurements using vector mesons with ALICE detector at the LHC
• Acceptance effects in the hyperons global polarization measurement
• Polarization in low energy kaon-hyperon interaction
• Low energy kaon-hyperon interaction
• Jet Propagation and Mach-Cone Formation in (3+1)-dimensional Ideal Hydrodynamics
• Spin-Vorticity Coupling for Massive Vector Mesons
• De Haas - van Alphen Effect under Rotation
• 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
• Spin alignment of vector mesons in heavy ion and proton - proton collisions
• Hyperon global polarization in heavy-ion collisions at NICA energies. Feed-down effects and the role of ${\Sigma }^0$ hyperons
• Centrality dependence of $p_T$ spectra for identified hadrons in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}=200$ GeV
• On chiral vortical effect in accelerated matter
• Alternative methods to measure global polarization of $\Lambda$ hyperons
• Spin Effects In Heavy Ion Collisions at High Energies
• Vortical waves in a quantum fluid with vector, axial, and helical charges. I. Non-dissipative transport
• Vorticity in the QGP liquid and hyperon polarization at the RHIC BES energies
• The Effect of Vorticity on QGP Thermodynamics
• Sphaleron Transition Rates and the Chiral Magnetic Effect
• Decorrelation of participant and spectator angular momenta in heavy-ion collisions
• Can CP-violation be observed in heavy-ion collisions?
• Helicity polarization in relativistic heavy ion collisions
• Jet Quenching in The Most Vortical Fluid: A Holographic Approach
• Some aspects of global Lambda polarization in heavy-ion collisions
• Global $\Lambda$ hyperon polarization in low-energy heavy ion collisions -- a scenario without vorticity
• Directed flow and rotation of transient matter
• Practical considerations for the effect of finite coverage on the azimuthal dependence of global spin alignment
• Quark-hadron duality in hydrodynamics: an example
• The Static Heavy Quark-Antiquark Potential within String Theory in Arbitrary Stationary Backgrounds