Local spin alignment of vector mesons in relativistic heavy-ion collisions

Abstract

We investigate the spin alignment of vector mesons arising from locally polarized quarks and anti-quarks (local spin alignment) in heavy-ion collisions. We find that ${\rho }_{00}\ne 1/3$ does not necessarily signal the global polarization of quarks and anti-quarks along the orbital angular momentum of the system, but may also originate from their local spin polarization. Such local spin polarization could be induced by local vorticity arising from the anisotropic expansion of the fireball. We further propose experimental observables that can distinguish between the local and the global spin alignments. Measurements of these observables in heavy-ion collisions can probe the vorticity pattern and shed light on the puzzles of $\varphi$ and $K^{\ast 0}$ spin alignments.

7 pages, 3 figures; version accepted by PLB

References in corpus (6)

• Angular momentum conservation in heavy ion collisions at very high energy
• Polarization probes of vorticity in heavy ion collisions
• Collective longitudinal polarization in relativistic heavy-ion collisions at very high energy
• Global quark polarization in non-central $A+A$ collisions
• Improved quark coalescence model for spin alignment and polarization of hadrons
• Polarized secondary particles in unpolarized high energy hadron-hadron collisions?

Cited by in corpus (31)

• Pattern of Global Spin Alignment of $\varphi$ and $K^{\ast 0}$ mesons in Heavy-Ion Collisions
• Properties of the QCD Matter -- An Experimental Review of Selected Results from RHIC BES Program
• Spin alignment of vector mesons in heavy-ion collisions
• Spin and polarization: a new direction in relativistic heavy ion physics
• Spin alignment of vector mesons by glasma fields
• Vorticity and Spin Polarization in Heavy Ion Collisions: Transport Models
• Pseudo-gauges and relativistic spin hydrodynamics for interacting Dirac and Proca fields
• Quantum kinetic theory for dynamical spin polarization from QED-type interaction
• Spin alignment of vector mesons by second-order hydrodynamic gradients
• Global spin polarization of multistrange hyperons and feed-down effect in heavy-ion collisions
• Vector meson's spin alignments in high energy reactions
• Spin polarization and correlation of quarks from glasma
• Spin alignment measurement of vector mesons produced in high energy collisions
• Quantum kinetic theory for spin transport of quarks with background chromo-electromagnetic fields
• Impact of globally spin-aligned vector mesons on the search for the chiral magnetic effect in heavy-ion collisions
• Spin alignment of vector mesons from quark dynamics in a rotating medium
• Rescattering effect on the measurement of K* spin alignment in heavy-ion collisions
• Transverse and longitudinal spin alignment from color fields in heavy ion collisions
• The spin alignment of vector mesons with light front quarks
• Vector and Tensor Spin Polarization for Vector Bosons at Local Equilibrium
• Quarkonium Polarization in Medium from Open Quantum Systems and Chromomagnetic Correlators
• Impact of strong magnetic field, baryon chemical potential, and medium anisotropy on polarization and spin alignment of hadrons
• First measurement of D${}^{\ast +}$ vector spin alignment in Pb$-$Pb collisions at $\sqrt{{\mathbf{s}}_{\mathrm{NN}}}=5.02$ TeV
• Kubo formulas for spin polarization in dissipative relativistic spin hydrodynamics: a first-order gradient expansion approach
• Spin Effects In Heavy Ion Collisions at High Energies
• Production of $K^{+}{K}^{-}$ Pairs Through Decay of $\varphi$ Meson
• Anomalous spin polarization from turbulent color fields
• Helicity polarization in relativistic heavy ion collisions
• Practical considerations for the effect of finite coverage on the azimuthal dependence of global spin alignment
• Practical Considerations for Measuring Global Spin Density Matrix Elements of Vector Mesons in Heavy-Ion Collisions
• Global hyperon polarization and effects of decay feeddown