2024/05/15 by M. Buzzegoli, Buzzegoli, M.
Physics and Astronomy · #FOS: Physical sciences #High-Energy Particle Collisions Research #Nuclear Theory (nucl-th) #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2405.09709
openalex publication_date 2024/05/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The vorticity is a quantity defined in a relativistic fluid that describes how much a fluid element is rotating and accelerating. By measuring the spin polarization of hadrons, it was found that the quark gluon plasma produced in heavy-ion collisions is the most "vorticous" fluid ever observed. More generally, this opens the possibility to study the physics of QCD matter using spin. Here I use statistical quantum field theory applied to a fluid in local thermodynamic equilibrium to show how to connect the average spin of a fermion with hydrodynamic quantities, and in particular with the thermal vorticity and the thermal shear. I show that the spin polarization of a Dirac particle induced by thermal vorticity is related to the gravitational (in medium) form factor related to spin-rotation coupling. For these reasons, as we are understanding the role of spin in hydrodynamics and in heavy-ion collisions, spin is becoming a promising tool to investigate the properties of QCD and whose applications are just begun to be explored.