Speaker
Tom Reichert
Description
The HADES experiment at GSI has recently provided data on the flow coefficients $v_1,...,v_4$ for protons in Au+Au reactions at $E_{\rm lab} = 1.23$ $A$GeV (or $\sqrt{s_\mathrm{NN}}=2.4$ GeV). This data allows to estimate the shear viscosity over entropy density ratio, $\eta/s$, at low energies via a coarse graining analysis of the UrQMD transport simulations of the flow harmonics in comparison to the experimental data. By this we can extract the space and time dependence of the $\eta/s$ ratio and provide for the first time an estimate of $\eta/s\approx0.65\pm0.15$ (or $(8\pm2)\,(4\pi)^{-1}$) for baryon rich matter at such low energies.
[1] T. Reichert, G. Inghirami and M. Bleicher, Phys.Lett.B 817 (2021) 136285
Primary author
Co-authors
Marcus Bleicher
Gabriele Inghirami
(GSI, Darmstadt)
