Speaker
Description
Recent O+O and Ne+Ne collisions at the LHC provide a controlled laboratory to test the applicability of relativistic hydrodynamics and search for signatures of quark-gluon plasma formation in small systems. We study O+O and Ne+Ne collisions at $\sqrt{s_{\mathrm{NN}}}=5.36~\mathrm{TeV}$ using two complementary approaches.
First, we compare viscous anisotropic hydrodynamics (VAH) with conventional viscous hydrodynamics (VH). After calibrating both frameworks to selected flow observables, we systematically scan higher-order flow harmonics and nonlinear flow correlations. The two frameworks give similar predictions over a broad centrality range, while appreciable differences emerge for selected observables toward peripheral collisions. These results quantify nonequilibrium effects and constrain the range of validity of conventional hydrodynamics.
Second, within the Hydro-Coal-Frag framework, we combine hydrodynamics at low $p_T$, quark coalescence at intermediate $p_T$, and fragmentation at high $p_T$. The calculations provide a good description of the available ALICE data and exhibit approximate number-of-constituent-quark scaling at intermediate $p_T$. This scaling provides an important signature of partonic degrees of freedom and QGP droplet formation in O+O and Ne+Ne collisions.
