Intrinsic Transverse Momentum Distribution of Jet Constituents in p-Pb Collisions at ALICE

The integral part of the URHIC program is also to study the pp and p–A collision in order to understand the “reference” (unmodified) particle production (in pp) and the “cold” nuclear phenomena in p–A. The main focus of this thesis is to study the parton shower evolution in p–Pb collisions in ALICE by analyzing jet fragmentation transverse momentum (j_{T} ). The analysis of j_{T} in p–Pb collisions, for which ALICE has a high quality data set, lays bases for later extension to pp and Pb–Pb data in order to study the induced gluon radiation. Additionally, the yields of \pi^0 meson were studied in Pb–Pb sqrt(s_{NN}) = 2.76 GeV collision. The \pi^0 analysis was followed for continuity of work with EMCal detector and as a complement to already progressing \pi^0 yield analysis in pp. The thesis also focuses on ALICE Electromagnetic Calorimeter (EMCal) and the single-photon Level-0 trigger. Development of the Level-0 trigger system was an important part of this work. From the data analysis point of view it is evident that without the L0 trigger it would be difficult to obtain many of the results presented in this thesis. EMCal is the sole large acceptance calorimeter in ALICE, which usage is crucial for full reconstruction of jets. Triggering in EMCal is important for enhancing sample of fully reconstructable jets.