The Effects of Pileup Events with 7 TeV Proton-Proton Collision Data in the LHC

The event analysis codes were developed to compare the magnitudes of track multiplicity, jet multiplicity, HT, MHT, MPT and |ΔØ| for the case of pileup and non-pileup events. And their correspondences between the Monte Carol simulation and the LHC 7 TeV proton-proton collision data were investigated. The event analysis codes executed HT, MHT, MPT and |ΔØ| calculations with jet, photon, CaloJets and vertex processes. All the data analysis was performed with CMSSW_3_8_4, SusyPAT, Root and CRAB. The event analysis and histogram codes were implemented by C and Python language respectively. The effects of pileup events were well shown in the track multiplicity. The correspondences between MC and collision data showed a good agreement with jet pT cut 30 GeV. The |ΔØ| distributions of QCD_ pT 30 GeV and collision data with jet pT cut 30 GeV were well agreed showing expected enhancements near 0 and π.