### Speaker

Ms
Jana Crkovska
(Czech Technical University in Prague)

### Description

Relativistic collisions of heavy ions produce a hot and dense matter similar to what existed in primordial Universe - the Quark-Gluon Plasma (QGP).
The hadronic collective flow was found to be one of the most pronounced signatures of the QGP.
Comparison of experimental data at RHIC energies with different hydrodynamical models revealed that the produced matter is not an ideal gas of quarks and gluons but rather a low viscous liquid.
Hydrodynamical calculations have also shown that the spatial anisotropy of the initial overlap zone of the nucleus-nucleus collisions is transferred into the final state momentum anisotropic flow.
The invariant differential cross section can be expanded into a Fourier series over the azimuthal angle, with flow harmonics figuring as Fourier coefficients.
At high energies the elliptic flow, defined by the second Fourier coefficient $v_2$, dominates the Fourier expansion for semi-peripheral and peripheral collisions. In central collisions the contribution of the third component $v_3$ becomes more pronounced due to the spatial initial state fluctuations.
Study of triangular flow in Pb+Pb collisions at $\sqrt{s_{NN}} = 2.76 \textup{ TeV}$ and in Au+Au collisions at $\sqrt{s_{NN}} = 200 \textup{ GeV}$ was performed using HYDJET++ Monte Carlo model. HYDJET++ combines a parametrized hydrodynamics for soft part of spectra with a microscopic jet quenching generator for hard and semi-hard collisions, giving a realistic prediction for different hadron species, such as $p$, $\pi$, $K$ or $\Lambda$. The model also enables study of influence of final-state interactions on flow of created hadrons. The interplay between jet physics and soft hydrodynamics, as well as
the influence of the resonance decays on the triangular flow in AA collisions at RHIC and LHC were studied. Reasons for violation of number-of-constituent-quark scaling at LHC will be discussed.

### Primary author

Ms
Jana Crkovska
(Czech Technical University in Prague)