Shear induced polarization: Collisional contributions

Abstract

It has been realized that thermal shear plays a similar role as thermal vorticity in polarizing spin of particles in heavy ion collisions. We point out that shear has a fundamental difference that it leads to particle redistribution in the medium. The redistribution gives rise to an additional contribution to spin polarization through the self-energy, which is parametrically the same order as the one considered so far in the literature. The self-energy contribution is in general gauge dependent. We introduce double gauge links stretching along the Schwinger-Keldysh contour to restore gauge invariance. We also generalize the straight path to adapt to the Schwinger-Keldysh contour. We find another contribution associated with the gauge link, which is also parametrically the same order. We illustrate the two contributions with a massive probe fermion in massless QED plasma with shear. A modest suppression of spin polarization is found from the combined contributions when the probe fermion has momentum much greater than the temperature.

arXiv comment29 pages, 5 figures

References in corpus (44)

• Global $\Lambda$ hyperon polarization in nuclear collisions: evidence for the most vortical fluid
• Event-by-event generation of electromagnetic fields in heavy-ion collisions
• Transport coefficients in high temperature gauge theories: (II) Beyond leading log
• Transport coefficients in high temperature gauge theories: (I) Leading-log results
• Effective Kinetic Theory for High Temperature Gauge Theories
• Spin Alignment of Vector Mesons in Non-central A+A Collisions
• Rotating quark-gluon plasma in relativistic heavy ion collisions
• Collective longitudinal polarization in relativistic heavy-ion collisions at very high energy
• Global quark polarization in non-central $A+A$ collisions
• Kinetic theory for massive spin-1/2 particles from the Wigner-function formalism
• Vortical fluid and $\Lambda$ spin correlations in high-energy heavy-ion collisions
• Shear-induced spin polarization in heavy-ion collisions
• Relativistic Chiral Kinetic Theory from Quantum Field Theories
• Local polarization and isothermal local equilibrium in relativistic heavy ion collisions
• 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
• Thermal vorticity and spin polarization in heavy-ion collisions
• Relativistic Quantum Kinetic Theory for Massive Fermions and Spin Effects
• Axial Kinetic Theory and Spin Transport for Fermions with Arbitrary Mass
• Spin polarization induced by the hydrodynamic gradients
• From Chiral Kinetic Theory To Relativistic Viscous Spin Hydrodynamics
• Quark Polarization in a Viscous Quark-Gluon Plasma
• Derivation of the nonlocal collision term in the relativistic Boltzmann equation for massive spin-1/2 particles from quantum field theory
• Relativistic second-order dissipative spin hydrodynamics from the method of moments
• Local spin polarization in high energy heavy ion collisions
• 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
• 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 Polarizations in a Covariant Angular-Momentum-Conserved Chiral Transport Model
• Covariant Spin Kinetic Theory I: Collisionless Limit
• Foundations and Applications of Quantum Kinetic Theory
• Quantum Kinetic Theory of Spin Polarization of Massive Quarks in Perturbative QCD: Leading Log
• A microscopic description for polarization in particle scatterings
• Local Equilibrium Spin Distribution From Detailed Balance
• Quantum Kinetic Theory for Quantum Electrodynamics
• Quantum kinetic theory for dynamical spin polarization from QED-type interaction
• Chiral Radiation Transport Theory of Neutrinos
• Chiral kinetic theory from the on-shell effective theory: derivation of collision terms
• Spin evolution of massive fermion in QED plasma
• Quantum kinetic theory for spin transport of quarks with background chromo-electromagnetic fields
• Massless Limit of Transport Theory for Massive Fermions
• Polarization Rotation of Chiral Fermions in Vortical Fluid

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• Spin alignment of quarkonia in vortical quark-gluon plasma
• Anisotropic linear waves and breakdown of the momentum expansion in spin magnetohydrodynamics
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• The Static Heavy Quark-Antiquark Potential within String Theory in Arbitrary Stationary Backgrounds
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