English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Within a parton cascade approach we investigate the scaling of thedifferential elliptic flow $v_2(p_T)$ with eccentricity $\epsilon_x$ and systemsize and its sensitivity to finite shear viscosity. We present calculations forshear viscosity to entropy density ratio $\eta/s$ in the range from $1/4\pi$ upto $1/\pi$, finding that the $v_2$ saturation value varies by about a factor 2.Scaling of $v_2(p_T)/\epsilon_x$ is seen also for finite $\eta/s$ whichindicates that it does not prove a perfect hydrodynamical behavior, but iscompatible with a plasma at finite $\eta/s$. Introducing a suitable freeze-outcondition, we see a significant reduction of $v_2(p_T)$ especially atintermediate $p_T$ and for more peripheral collisions. This causes a breakingof the scaling for both $v_2(p_T)$ and the $p_T-$averaged $v_2$, while keepingthe scaling of $v_2(p_T)/\la v_2\ra$. This is in better agreement with theexperimental observations and shows as a first indication that the $\eta/s$should be significantly lower than the pQCD estimates. We finally point out thenecessity to include the hadronization via coalescence for a definiteevaluation of $\eta/s$ from intermediate $p_T$ data.

Scalings of Elliptic Flow for a Fluid at Finite Shear Viscosity