Inspecting High Density Matter with CMS Experiment

Abstract

The quark-gluon plasma (QGP), conjectured to have existed in the very beginning ofthe universe evolution, reflects the asymptotic freedom property of Quantum Chromody-namics, the theory governing the strong force. The QGP was recreated in the laboratoryby experiments at RHIC at the LHC via very high energy heavy ions (HI) collisions,producing a state of matter at high densities and temperatures. The QGP was found tobehave as a strongly coupled almost perfect fluid, revealing a collective behavior amongthe produced particles. Intriguingly, evidence of systems produced with similar collectivecharacteristics were gathered later, in much smaller proton-proton (pp) and proton-ion(pA) collisions at the LHC and at RHIC, in events where a very large number of particleswere produced. The reasons for those similarities are under vigorous debate and intenseexperimental and theoretical scrutiny. The common ground in those findings are foundin experimental data involving correlations of particles produced in pp, pA and ion-ion(AA) collisions at very high energies, which is the main object of investigation of thisPost-Doctoral research project.