Systematics and efficiencies for the multiplicity dependent D*+ meson measurement in 7 TeV proton-proton collisions at ALICE

Abstract

This thesis focuses on the extraction of the raw yield of reconstructed D∗+ mesons and its systematics and efficiency in different pT and multiplicity intervals in proton-proton collisions at √s = 7 TeV. The yield is extracted from data samples required from the ALICE detector measured in 2010 over four time periods with topological selection and 3σ particle identification (PID) cuts. The purpose of this work is to analyze the open charm production dependence on the multiplicity. It is expected that the production probability would increase with multiplicity due to the increase in the hardness of the collision. However, if multi-parton interactions play a large role at LHC we can expect the increase to be much more steep than what is expected from theoretical models based on single-parton interactions. The final result of the D∗+ vs multiplicity analysis is expected to increase the knowledge of the multi-parton interaction phenomena.