Results on Minimum Bias Interactions, Underlying Events and Particles Production from ATLAS

Measurements of the properties of charged particle production are presented from proton­-proton collisions at different centre­-of­-mass energies in the range of 0.9 to 13 TeV and compared to various Monte Carlo event generator models. Furthermore particle distributions sensitive to the underlying event in proton­-proton collisions have been measured and are compared to theoretical models. The production properties of mesons and baryons are presented and compared to predictions. The effects of space-­time geometry in the hadronization phase has been studied in the context of Bose­-Einstein correlations between charged particles, for determining the size and shape of the source from which particles are emitted and for interpreting of quark confinement effects. Bose­-Einstein correlation parameters are investigated in p­p collisions at 900 GeV and 7 TeV, up to very high charged­-particle multiplicities.