Charged particle production in diffractive proton-proton scattering at the RHIC and LHC energies

In this thesis, measurements of charged-particle distributions in diffractive interactions are presented using data collected in year 2015 by the STAR experiment at RHIC and the ATLAS experiment at the LHC. The most important results of these analyses are multiplicity distributions of charged particles and their densities as a function of transverse momentum and pseudorapidity. Additionally, the mean transverse momentum as a function of charged-particle multiplicity, as well as, the distributions of the fractional energy loss of the forward-scattered proton, $\xi$, and the square of the four- momentum transfer, $-t$, are measured using ATLAS data. The results are compared to the predictions of several models, implemented in MC generators, namely EPOS, QGSJET, HERWIG and different tunes of PYTHIA 8. Most of these models give reasonable description of STAR data and do not sufficiently reproduce ATLAS data. Both STAR and ATLAS analyses are completed with the identified particle/antiparticle (pion, kaon, proton and their antiparticles) ratios as a function of transverse momentum. A significant asymmetry in the antiproton-proton production ratios at $0.02 < \xi < 0.05$ is measured using STAR data, indicating a non-negligible transfer of the baryon number from the forward to the central region.