Local and global polarization of $\Lambda$ hyperons across RHIC-BES energies: the roles of spin hall effect, initial condition and baryon diffusion

Abstract

We perform a systematic study on the local and global spin polarization of $\Lambda$ and $\overline{\Lambda }$ hyperons in relativistic heavy-ion collisions at beam energy scan energies via the (3+1)-dimensional CLVisc hydrodynamics model with AMPT and SMASH initial conditions. Following the quantum kinetic theory, we decompose the polarization vector as the parts induced by thermal vorticity, shear tensor and the spin Hall effect (SHE). We find that the polarization induced by SHE and the total polarization strongly depends on the initial conditions. At $7.7$GeV, SHE gives a sizeable contribution and even flips the sign of the local polarization along the beam direction for AMPT initial condition, which is not observed for SMASH initial condition. Meanwhile, the local polarization along the out-of-plane direction induced by SHE with AMPT initial condition does not always increase with decreasing collision energies. Next, we find that the polarization along the beam direction is sensitive to the baryon diffusion coefficient, but the local polarization along the out-of-plane direction is not. Our results for the global polarization of $\Lambda$ and $\overline{\Lambda }$ agree well with the STAR data. Interestingly, the global polarization of $\overline{\Lambda }$ is not always larger than that of $\Lambda$ due to various competing effects. Our findings are helpful for understanding the polarization phenomenon and the detailed structure of quark-gluon plasma in relativistic heavy-ion collisions.

arXiv comment13 pages, 8 figures

References in corpus (141)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Brief Introduction to PYTHIA 8.1
• A Multi-Phase Transport Model for Relativistic Heavy Ion Collisions
• Global $\Lambda$ hyperon polarization in nuclear collisions: evidence for the most vortical fluid
• HIJING 1.0: A Monte Carlo Program for Parton and Particle Production in High Energy Hadronic and Nuclear Collisions
• Berry Curvature, Triangle Anomalies, and the Chiral Magnetic Effect in Fermi Liquids
• Globally Polarized Quark-gluon Plasma in Non-central A+A Collisions
• ZPC 1.0.1: a parton cascade for ultrarelativistic heavy ion collisions
• Chiral Kinetic Theory
• Angular momentum conservation in heavy ion collisions at very high energy
• Relativistic distribution function for particles with spin at local thermodynamical equilibrium
• The importance of the bulk viscosity of QCD in ultrarelativistic heavy-ion collisions
• Particle production and equilibrium properties within a new hadron transport approach for heavy-ion collisions
• Kinetic theory with Berry curvature from quantum field theories
• Global hyperon polarization at local thermodynamic equilibrium with vorticity, magnetic field and feed-down
• Collective flow in p-Pb and d-Pb collisions at TeV energies
• Small System Collectivity in Relativistic Hadron and Nuclear Collisions
• Berry curvature and 4-dimensional monopole in relativistic chiral kinetic equation
• Spin Alignment of Vector Mesons in Non-central A+A Collisions
• Chiral anomaly and local polarization effect from quantum kinetic approach
• Rotating quark-gluon plasma in relativistic heavy ion collisions
• Relativistic fluid dynamics with spin
• Study of Lambda polarization in relativistic nuclear collisions at sqrt{s}_NN = 7.7-200 GeV
• Polarization of $\Lambda$ ($\bar{\Lambda }$) hyperons along the beam direction in Au+Au collisions at $\sqrt{s_{{}_{NN}}}$ = 200 GeV
• Collective dynamics of the high-energy proton-nucleus collisions
• Polarization probes of vorticity in heavy ion collisions
• Lorentz Invariance in Chiral Kinetic Theory
• Effects of initial flow velocity fluctuation in event-by-event (3+1)D hydrodynamics
• Vorticity in Heavy-Ion Collisions
• A study of vorticity formation in high energy nuclear 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
• Polarization and Vorticity in the Quark Gluon Plasma
• Kinetic theory for massive spin-1/2 particles from the Wigner-function formalism
• Relativistic hydrodynamics for spin-polarized fluids
• Vortical fluid and $\Lambda$ spin correlations in high-energy heavy-ion collisions
• Shear-induced spin polarization in heavy-ion collisions
• Lambda Polarization in Peripheral Heavy Ion Collisions
• Polarization of massive fermions in a vortical fluid
• Fate of spin polarization in a relativistic fluid: An entropy-current analysis
• Relativistic Chiral Kinetic Theory from Quantum Field Theories
• Local polarization and isothermal local equilibrium in relativistic heavy ion collisions
• Elliptic and triangular flow in p+Pb and peripheral Pb+Pb collisions from parton scatterings
• Probing vorticity structure in heavy-ion collisions by local $\Lambda$ polarization
• Generating spin polarization from vorticity through nonlocal collisions
• Spin-thermal shear coupling in a relativistic fluid
• Pseudorapidity distribution and decorrelation of anisotropic flow within CLVisc hydrodynamics
• Net baryon diffusion in fluid dynamic simulations of relativistic heavy-ion collisions
• Thermal vorticity and spin polarization in heavy-ion collisions
• Collisions in Chiral Kinetic Theory
• Eccentric protons? Sensitivity of flow to system size and shape in p+p, p+Pb and Pb+Pb collisions
• Flow Vorticity in Peripheral High Energy Heavy Ion Collisions
• Nonlinear Responses of Chiral Fluids from Kinetic Theory
• Lambda hyperon polarization in relativistic heavy ion collisions from the chiral kinetic approach
• Relativistic dissipative spin dynamics in the relaxation time approximation
• Relativistic Quantum Kinetic Theory for Massive Fermions and Spin Effects
• Spin tensor and its role in non-equilibrium thermodynamics
• Spin Hydrodynamics and Symmetric Energy-Momentum Tensors -- A current induced by the spin vorticity --
• Equation of state at finite densities for QCD matter in nuclear collisions
• Hydrodynamics of spin currents
• Relativistic spin hydrodynamics with torsion and linear response theory for spin relaxation
• Axial Kinetic Theory and Spin Transport for Fermions with Arbitrary Mass
• Spin polarization induced by the hydrodynamic gradients
• Non-dissipative second-order transport, spin, and pseudo-gauge transformations in hydrodynamics
• The ideal relativistic fluid limit for a medium with polarization
• Spin-dependent distribution functions for relativistic hydrodynamics of spin-1/2 particles
• Anomalous chiral transports and spin polarization in heavy-ion collisions
• Derivation of the nonlocal collision term in the relativistic Boltzmann equation for massive spin-1/2 particles from quantum field theory
• Elliptic and triangular flow anisotropy in deuteron-gold collisions at RHIC and proton-lead collisions at the LHC
• Thermodynamic versus kinetic approach to polarization-vorticity coupling
• The ideal relativistic spinning gas: polarization and spectra
• Collective flow in 2.76 A TeV and 5.02 A TeV Pb+Pb collisions
• Local spin polarization in high energy heavy ion collisions
• Effects of bulk viscosity and hadronic rescattering in heavy ion collisions at RHIC and LHC
• From Kadanoff--Baym to Boltzmann equations for massive spin-1/2 fermions
• Reexamination of local spin polarization beyond global equilibrium in relativistic heavy ion collisions
• Mass Correction to Chiral Kinetic Equations
• Effective quantum kinetic theory for spin transport of fermions with collsional effects
• A hydrodynamic study of hyperon spin polarization in relativistic heavy ion collisions
• Spin polarization evolution in a boost invariant hydrodynamical background
• Decorrelation of anisotropic flows along the longitudinal direction
• Vorticity in low-energy heavy-ion collisions
• Spin Polarizations in a Covariant Angular-Momentum-Conserved Chiral Transport Model
• Hydrodynamic Collectivity in Proton--Proton Collisions at 13 TeV
• Covariant Spin Kinetic Theory I: Collisionless Limit
• Longitudinal spin polarization in a thermal model
• Feed-down effect on $\Lambda$ spin polarization
• The smallest fluid on earth
• Probing the partonic degrees of freedom in high multiplicity p-Pb collisions at $\sqrt{s_{NN}}=$ 5.02 TeV
• Quantum Kinetic Theory of Spin Polarization of Massive Quarks in Perturbative QCD: Leading Log
• Polarization transfer in hyperon decays and its effect in relativistic nuclear collisions
• Spin Hall effect in heavy ion collisions
• (3+1)-D viscous hydrodynamics CLVisc at finite net baryon density: identified particle spectra, anisotropic flows and flow fluctuations across BES energies
• Global and local spin polarization in heavy ion collisions: a brief overview
• Wounded quarks in A+A, p+A, and p+p collisions
• Different space-time freeze-out picture -- an explanation of different $\Lambda$ and $\bar{\Lambda }$ polarization?
• Particle Production via Strings and Baryon Stopping within a Hadronic Transport Approach
• Sound waves and vortices in a polarized relativistic fluid
• Beam Energy Dependence of Jet-Quenching Effects in Au+Au Collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, and 62.4 GeV
• Analytic solutions of relativistic dissipative spin hydrodynamics with Bjorken expansion
• A microscopic description for polarization in particle scatterings
• Kinetic equations for massive Dirac fermions in electromagnetic field with non-Abelian Berry phase
• Perfect-fluid hydrodynamics with constant acceleration along the stream lines and spin polarization
• From hydro to jet quenching, coalescence and hadron cascade: a coupled approach to solving the $R_{AA}\otimes v_2$ puzzle
• Vorticity and particle polarization in heavy ion collisions (experimental perspective)
• Relaxation Time for Strange Quark Spin in Rotating Quark-Gluon Plasma
• QCD Equation of State at Finite Chemical Potentials for Relativistic Nuclear Collisions
• Side-Jump Induced Spin-Orbit Interaction of Chiral Fluids from Kinetic Theory
• Global $\Lambda$ polarization in moderately relativistic nuclear collisions
• Longitudinal fluctuations and decorrelations of anisotropic flows at the LHC and RHIC energies
• Polarization in relativistic fluids: a quantum field theoretical derivation
• Vorticity and Spin Polarization --- A Theoretical Perspective
• Hyperon Polarization from the Vortical Fluid in Low Energy Nuclear Collisions
• Influence of the neutron-skin effect on nuclear isobar collisions at RHIC
• Quantum Kinetic Theory for Quantum Electrodynamics
• Spin Polarization Formula for Dirac Fermions at Local Equilibrium
• Effect of thermal shear on longitudinal spin polarization in a thermal model
• Nonlinear Chiral Transport Phenomena
• Hydrodynamic helicity polarization in relativistic heavy ion collisions
• Vortex rings from high energy central p+A collisions
• Chiral kinetic theory from the on-shell effective theory: derivation of collision terms
• Quantum kinetic theory for spin-1/2 fermions in Wigner function formalism
• Evolution of $\Lambda$ polarization in the hadronic phase of heavy-ion collisions
• Benchmarking a Non-Equilibrium Approach to Photon Emission in Relativistic Heavy-Ion Collisions
• Modified equilibrium distributions for Cooper--Frye particlization
• Collisional strong-field QED kinetic equations from first principles
• From Chiral Kinetic Theory To Spin Hydrodynamics
• Polarization Rotation of Chiral Fermions in Vortical Fluid
• Mass Correction to Chiral Kinetic Equations
• The quantum kinetic equation and dynamical mass generation in 2+1 Dimensions
• Relativistic decomposition of the orbital and the spin angular momentum in chiral physics and Feynman's angular momentum paradox
• Signatures of the spin Hall effect in hot and dense QCD matter
• Recent developments in chiral and spin polarization effects in heavy-ion collisions
• Power corrections and gradient expansion in QED transport theory
• Damping and polarization rates in near equilibrium state
• Collective flow at SIS energies within a hadronic transport approach: Influence of light nuclei formation and equation of state
• Asymmetric longitudinal flow decorrelations in proton-nucleus collisions
• Particlization in fluid dynamical simulations of heavy-ion collisions: The iS3D module
• Helicity polarization in relativistic heavy ion collisions

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• The QCD phase diagram and Beam Energy Scan physics: a theory overview
• Quantum kinetic theory for dynamical spin polarization from QED-type interaction
• Lorentz-covariant nonlocal collision term for spin-1/2 particles
• Splitting of proton-antiproton directed flow in relativistic heavy-ion collisions
• Spin evolution of massive fermion in QED plasma
• Anomalous magnetohydrodynamics with temperature-dependent electric conductivity and application to the global polarization
• Hyperon polarization and its relation with directed flow in high-energy nuclear collisions
• Spin polarization induced by magnetic field and the relativistic Barnett effect
• An introduction to relativistic spin hydrodynamics
• Cross effects in spin hydrodynamics: A revisit Entropy analysis and statistical operator
• Directed flow and global polarization in Au+Au collisions across energies covered by the beam energy scan at RHIC
• Collisional corrections to spin polarization from quantum kinetic theory using Chapman-Enskog expansion
• Emergent Canonical Spin Tensor in the Chiral-Symmetric Hot QCD
• Collective dynamics of polarized spin-half fermions in relativistic heavy-ion collisions
• Impact of strong magnetic field, baryon chemical potential, and medium anisotropy on polarization and spin alignment of hadrons
• Spin alignment of quarkonia in vortical quark-gluon plasma
• Investigate the $\Lambda$ and $\bar{\Lambda }$ polarization splitting effect with combined mechanisms
• Estimating Longitudinal Polarization of $\Lambda$ and $\bar{\Lambda }$ Hyperons at Relativistic Energies using Hydrodynamic and Transport models
• Polarization in heavy ion collisions: a theoretical review
• Global $\Lambda$ polarization in heavy-ion collisions at high baryon density
• Spin Boltzmann equation for non-relativistic spin-1/2 fermions
• An improved formula for Wigner function and spin polarization in a decoupling relativistic fluid at local thermodynamic equilibrium