Femtoscopic analysis of identical charged kaons in Pb-Pb collisions at 5.02 TeV.

Heavy-ion collisions at the LHC are believed to produce quark-gluon plasma (QGP), which is a state of matter with unbound partons. It behaves similarly to a (nearly) perfect fluid which is revealed by the presence of, for example, collective effects. The space-time properties of a QGP fireball can be studied using femtoscopic correlations, which allow to determine the spatial size of a particle-emitting, to study its evolution dynamics and collective flow effects, etc. In this communication, we report results of one- and three-dimensional femtoscopic analyses of identical charged-kaon correlations in Pb-Pb collisions at 5.02 TeV measured by the ALICE experiment. The importance of kaon femtoscopy is to check if different model scenarios work equally well as for pions. The results show the presence of radial expansion of an emission source ($i.e.$, radial flow). The extracted one-dimensional radii presented as a function of collision multiplicity are compared with kaon source sizes obtained for different energy, Pb-Pb at 2.76 TeV, and collision systems: p-Pb at 5.02 TeV, and pp at 7 TeV. A comparison with calculations from the integrated hydrokinetic model (iHKM) is also performed.