Analysis of Z boson production in the electron channel with the CMS detector at the LHC

A Monte Carlo (MC) analysis of Z bosons, based on the selection of electrons and positrons which will be produced at the LHC, is presented. In doing so, a full simulation based on the CMS detector was taken into account. Owing to a lack of data, a small dataset, so called pseudo data, with an integrated luminosity of 10 pb 1 , at a center-of-mass energy of 10 TeV, was used. A simple and robust electron/positron selection procedure for the central part of the detector was devised. It was shown that this selection leads to practically background free sample of Z bosons. Based on the Z boson counting, with a statistical uncertainty of 3%, an efficiency correction of 3% and the uncertainty on the integrated luminosity of about 11%, the Z boson cross-section could be calculated and compared to its theoretical value. In addition, the same counting method was used to calculate the integrated luminosity to 6%, which is mainly due to a theoretical uncertainty of about 5%. Various distributions, such as rapidity and transversal momentum, were also considered and compared to the complete (1:4 fb 1 ) MC simulation. The Z boson transverse momentum and rapidity spectrum measurement was then calculated. It was shown that such measurements with an integrated luminosity of 10 pb 1 at 10 TeV are possible, with accuracies consistent with present knowledge. A small test with real data was performed and showed an nice agreement between data and MC simulation.