Speaker
Ms
Nadezda Chernyavskaya
(ITEP)
Description
The dependence of the spectra shape of produced charged hadrons on the size of a colliding system is discussed using a two component model. As a result, the hierarchy by the system-size in the spectra shape is observed. Next, the extension of the two component model accounting for the 'collective flow' using recent theoretical calculations is suggested to describe the spectra of charged particles produced in heavy-ion collisions in the full range of transverse momenta, pT. Data from heavy-ion collisions measured at RHIC and LHC are analyzed using the introduced approach and are combined in terms of energy density. The Boltzmann-like statistical distribution taking into account the 'collective flow' effects stands for the radiation of the thermalized particles, while the power-like term describes charged hadron production in pQCD. The observed regularities give understanding of the peculiar shape of the nuclear modification factor, $R_{AA}$, as a function of transverse momentum, $p_T$, and might be explained by the formation of QGP during the collision.