Revealing the source of the radial flow patterns in proton--proton collisions using hard probes

Understand

In this work, we propose a tool to reveal the origin of the collective-like phenomena observed in proton--proton collisions.

• We exploit the fundamental difference between the underlying mechanisms, color reconnection (CR) and hydrodynamics, which produce radial flow patterns in \textsc{Pythia}~8 and \textsc{Epos}~3, respectively.
• Specifically, we proceed by examining the strength of the coupling between the soft and hard components which, by construction, is larger in \textsc{Pythia}~8 than in \textsc{Epos}~3.
• We study the transverse momentum ($p_{\rm T}$) distributions of charged pions, kaons and (anti)protons in inelastic pp collisions at $\sqrt{s}=$ 7\,TeV produced at mid-rapidity.