Speaker
Description
In the high-energy physics, particularly within the context of heavy-ion collisions conducted at the Large Hadron Collider (LHC), there exists a puzzle where viscous hydrodynamics fails to accurately depict the experimental data for the second and third flow harmonics, $v_{2}\{2 \}$ and $v_{3}\{2 \}$, in ultra-central Pb + Pb collisions at 2.76 TeV. This study proposes a novel approach to address this issue by reducing the initial state fluctuations through the augmentation of the minimum inter-nucleon distance within the nucleus. It was observed that increasing this minimum distance resulted in a reduction of the initial eccentricity, as compared to the predictions made by the Woods-Saxon model. Consequently, a lower ratio of shear viscosity to entropy density, $\eta / s$, is necessitated. Employing the TRENTo model, this research calculated the eccentricities within the $0–1 \%$ centrality class and subsequently determined the flow harmonic coefficients $v_2\{2 \}$ and $v_3 \{2\}$ using the (3+1) dimensional viscous hydrodynamics models CLVisc. By comparing various scenarios with different minimum distances between nucleons, this study discovered that a reduction in initial state fluctuations has a substantial impact on resolving the aforementioned puzzle within the nucleus of Pb. This conclusion not only addresses the specific issue of flow harmonic discrepancies but also contributes to a broader understanding of the initial state conditions in heavy-ion collisions. By refining our models to better reflect the true initial conditions, this study enhances the predictive capabilities of hydrodynamic simulations, thereby advancing the field of high-energy physics.
