May 17 – 22, 2021
US/Eastern timezone

Thermalization time constrained by high-pt QGP tomography

May 21, 2021, 10:10 AM
Room A (Zoom)

Room A


zoom co-host: Niveditha Ramasubramanian
Theory talk Other Bulk (Small systems)


Mr Stefan Stojku (Institute of Physics University of Belgrade)


We show that high-$p_{\perp}$ $R_{AA}$ and $v_2$ are way more sensitive to the QGP thermalization time, $\tau_0$, than the distributions of low-$p_{\perp}$ particles, and that the high-$p_{\perp}$ observables prefer relatively late thermalization at $\tau_0$ ∼ 1 fm/c. To calculate high-$p_{\perp}$ $R_{AA}$ and $v_2$, we employ our newly developed DREENA-A formalism, which combines state-of-the-art dynamical energy loss model with 3+1 dimensional hydrodynamical simulations. The model applies to both light and heavy flavor, and we predict a larger sensitivity of heavy observables to the thermalization time. Elliptic flow parameter $v_2$ is also more sensitive to $\tau_0$ than $R_{AA}$ due to non-trivial differences in the evolution of in-plane and out-of-plane temperature profiles. This presents the first time when a parameter describing bulk QGP has been constrained by high-$p_{\perp}$ observables and related theory, i.e., by so-called QGP tomography.

Primary authors

Mr Stefan Stojku (Institute of Physics University of Belgrade) Dr Jussi Auvinen (Institute of Physics University of Belgrade) Prof. Marko Djordjevic (University of Belgrade Faculty of Biology) Dr Pasi Huovinen (Institute of Physics University of Belgrade) Dr Magdalena Djordjevic (Institute of Physics University of Belgrade)

Presentation materials