A solvable model for spin polarizations with flow-momentum correspondence

TL;DR

This paper introduces an analytically solvable model for spin polarizations in heavy-ion collisions, linking flow dynamics to spin behavior and revealing symmetries between different flow contributions.

Contribution

It provides a new analytical model based on the blast-wave picture that explicitly connects flow patterns to spin polarization phenomena in heavy-ion collisions.

Findings

Spin polarization with respect to the reaction plane is governed by directed flow.

Along the beam direction, polarization is influenced by flow ellipticity.

The model reveals a symmetry between vorticity and shear stress contributions.

Abstract

We present an analytically solvable model based on the blast-wave picture of heavy-ion collisions with flow-momentum correspondence. It can describe the key features of spin polarizations in heavy-ion collisions. With the analytical solution, we can clearly show that the spin polarization with respect to the reaction plane is governed by the directed flow, while the spin polarization along the beam direction is governed by the ellipticity in flow and in transverse emission area. There is a symmetry between the contribution from the vorticity and from the shear stress tensor due to the flow-momentum correspondence. The solution can be improved systematically by perturbation method.