Net-charge fluctuation analysis in Ar+Sc interactions at beam momentum 75 GeV/c

The goal of the ion programme of NA61/SHINE experiment is the search of the critical point of strongly interacting matter. NA61/SHINE performs scan of the phase diagram of strongly interacting matter by studying collisions of different size systems (p+p, Be+Be, Ar+Sc, Xe+La, Pb+Pb) at different energies (beam momentum in the range of 13A - 158A GeV/c). Results presented in this thesis are important part of this study. The critical point signature is the rapid change of the multiplicity and net-charge fluctuations in the neighbourhood of the critical point. The analysis was performed for Ar+Sc collisions at beam momentum 75A GeV/c. In this thesis intensive (scaled variance, skewness, kurtosis) and strongly intensive (Ω[N,E P ], strongly intensive cumulants) quantities were calculated with the use of central and algebraic moments of multiplicity and net-charge distributions. Their behaviour as a function of the width of centrality bin was analysed. Obtained results were compared with p+p NA61/SHINE results. The statistical uncertainties were obtained with the use of bootstrap method and compared to uncertainties obtained by using subsamples method. Systematical uncertainties were not included in presented analysis. No conclusions concerning the critical point presence can be made basing on presented research as the rest of energies and systems has to be analysed as well.