# Quark Matter 2017

5-11 February 2017
Hyatt Regency Chicago
America/Chicago timezone

## Beam Energy and System Size Dependence of the Viscous Damping of Anisotropic Flow

Not scheduled
2h 30m
Hyatt Regency Chicago

#### Hyatt Regency Chicago

151 East Wacker Drive Chicago, Illinois, USA, 60601
Board: C08
Poster

### Speaker

Mr Niseem Abdelrahman"Magdy" (Stony Brook University)

### Description

We present recent STAR measurements of the anisotropic flow coefficients $v_n$ ($n = 1-6$) in Au+Au, Cu+Cu, Cu+Au collisions at $\sqrt{s_{NN}} = 200$~GeV and U+U collisions at $\sqrt{s_{NN}} = 193$~GeV and for Au+Au collisions spanning the full range of the first beam energy scan ($7 - 200$~GeV: BES-I). For a given beam energy, the differential $v_n$ measurements indicate acoustic scaling patterns which reflect the detailed dependence of $v_n$ on collision-system size, eccentricity ($\varepsilon_n$), temperature ($T$) and chemical potential ($\mu_{B}$). These measurements are important constraints for the $\sqrt{s_{NN}}$ dependence of the viscous coefficient which encode the $T$ and $\mu_{B}$ dependence of the specific shear viscosity $\eta/s$. The beam energy dependence of the viscous coefficient for a fixed centrality, shows a non-monotonic pattern which could be an indication for the onset of critical reaction dynamics in the BES-I energy range.

Collaboration STAR Collective Dynamics

### Primary author

Mr Niseem Abdelrahman"Magdy" (Stony Brook University)