2025/01/26 by Noah M. MacKay, MacKay, Noah M.
Physics and Astronomy · #81T28 #81V05 #82B30 #82B40 #FOS: Physical sciences #High-Energy Particle Collisions Research #Nuclear Theory (nucl-th) #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics
paper · pdf · doi:10.48550/arxiv.2501.15658
openalex publication_date 2025/01/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Transport properties of the quark-gluon plasma are instrumental to testing perturbative quantum chromodynamics and understanding the extreme conditions of relativistic heavy-ion collisions. This study presents an analytical investigation of the shear viscosity η and the shear viscosity-to-entropy density ratio η/s of the QGP using a novel multi-component Chapman-Enskog framework assuming full thermalization. The approach incorporates species-specific contributions from gluons and (anti-)quarks into the plasma shear viscosity, temperature-dependent running parameters for the Debye mass and strong coupling, and a time-dependent cooling model. Our findings show that both η and η/s are enhanced by the inclusion of (anti-)quarks with gluons, and the parameters decrease over time due to the cooling and expansion of the QGP. These results align with perturbative QCD predictions, offering a more optimistic representation of QGP transport properties under dynamic conditions. This multi-component framework is compared with a multi-phase transport model that treats the QGP as a gluon gas with (anti-)quark augmentation.