Abstract
The understanding of heavy ion collisions and its quark-gluon plasma (QGP) formation requires a complicated interplay of rich physics in a wealth of experimental data. In this work we compare for identified particles the transverse momentum dependence of both the yields and the anisotropic flow coefficients for both PbPb and pPb collisions. We do this in a global model fit including a free streaming prehydrodynamic phase with variable velocity vfs, thereby widening the scope of initial conditions. During the hydrodynamic phase we vary three second order transport coefficients. The free streaming velocity has a preference slightly below the speed of light. In this extended model the QGP bulk viscosity is small and even consistent with zero.
| Original language | English |
|---|---|
| Article number | 202301 |
| Pages (from-to) | 1-6 |
| Number of pages | 6 |
| Journal | Physical Review Letters |
| Volume | 126 |
| Issue number | 20 |
| DOIs | |
| Publication status | Published - 20 May 2021 |
Funding
We are grateful to Jonah Bernhard and Scott Moreland for making their codes public together with an excellent documentation. We thank Steffen Bass, Aleksas Mazeliauskas, Ben Meiring, and Urs Wiedemann for discussions. G. N. is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under grant Contract No. DE-SC0011090.