Large mass dimuon detection in the LHCb experiment

The structure of this thesis consists of two main parts: in the first part (Detector studies), the work is focused on the performances of the Multiwire Proportional Chambers, adopted for the detection of muons in LHCb, while in the second part (Physics studies) it is focused on the study of the LHCb potentialities to improve the knowledges of the proton Parton Distribution Functions with the physical channel Z0 -> mu+ mu-. The work described in the first part is concentrated on the cosmic rays test station developed in Rome2 in order to carry out the study of the detectors performances. In particular, the cosmic rays stand allows to perform a detailed study of the detector tracking capabilities and to obtain precise measurements of the efficiency and gas gain uniformity of the produced chambers. In the second part of the thesis is reported a study of the process pp -> Z0 -> mu+ mu-. The aim of the study is to demonstrate that, in spite of the limited angular acceptance and the optimization for a different kind of physics, the number of Z0 detected at LHCb is sufficient to make profitable physics. Moreover, the foward design of the spectrometer allows to study the proton structure in a kinematic region not probed by the present experiments. A particular focus has been put on the effect of the LHCb geometrical acceptance on the cross section sensitivity to the various set of partons, simulating the process with two event generators, PYTHIA and MC@NLO.