Spin Effects In Heavy Ion Collisions at High Energies

Abstract

In non-central high energy heavy ion collisions, the colliding system possesses a huge orbital angular momentum along the normal direction of the reaction plane. Due to the spin orbit interaction in the system, such a huge orbital angular momentum leads to the spin polarization of quarks and anti-quarks in the quark matter system produced in the collision. Such an effect, known as the global polarization effect, was predicted many years ago and has been confirmed by the STAR collaboration at RHIC. The discovery of the global polarization effect opens a new avenue in heavy ion physics in general and in studying the properties of quark-gluon plasma in particular. This talk will briefly review the original ideas and calculations that lead to the prediction and summarize progresses and problems in related aspects.

plenary talk at the 24th International Spin Symposium (SPIN2021)

References in corpus (14)

• Angular momentum conservation in heavy ion collisions at very high energy
• Chiral anomaly and local polarization effect from quantum kinetic approach
• 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
• Shear-induced spin polarization in heavy-ion collisions
• Spin-thermal shear coupling in a relativistic fluid
• Global $\Lambda$ Polarization in high energy collisions
• Global polarization measurement in Au+Au collisions
• Lambda hyperon polarization in relativistic heavy ion collisions from the chiral kinetic approach
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• Magnetic field effects in peripheral heavy-ion collisions around 1 GeV/nucleon