Collective flow in single-hit QCD kinetic theory

Motivated by recent interest in collectivity in small systems, we calculate the harmonic flow response to initial geometry deformations within weakly coupled QCD kinetic theory using the first correction to the free-streaming background. We derive a parametric scaling formula that relates harmonic flow in systems of different sizes and different generic initial gluon distributions. We comment on similarities and differences between the full QCD effective kinetic theory and the toy models used previously. Finally we calculate the centrality dependence of the integrated elliptic flow v(2) in oxygen-oxygen, proton-lead and proton-proton collision systems.

Automated summary

This study focuses on the collective behavior in small systems and calculates the harmonic flow response to initial geometry deformations using weakly coupled QCD kinetic theory. A parametric scaling formula is derived to relate harmonic flow in different size systems with generic initial gluon distributions. The study also compares the full QCD effective kinetic theory with previous toy models. Finally, the centrality dependence of integrated elliptic flow v(2) is calculated in various collision systems.