• CMS
• LHC
• momentum
• muon
• resolution

In the framework of the Standard Model, the electroweak theory predicts relations among observables which can be measured. After the discovery of the Higgs boson, all the parameters of the Standard Model are known and it is thus possible to predict those observables with increasing precision in order to test the consistency of the model. A small deviation of measured values from those prediction would be an indirect hint of physics beyond the Standard Model.

In particular, the mass of the W boson has a far smaller uncertainty in the theoretical prediction than in the measured value. For this reason, an accurate measurement of the W mass would provide such a test of validity of the Standard Model.

In order to achieve the precision required to have a fair comparison with the theory, it is necessary to control the distributions of the variables entering the measurement at the permil level or even better. The CMS experiment is planning to deliver a precise measurement of W mass within the next years, analysing events of W decaying to a muon and a neutrino.

One of the main systematics on the measurements is the knowledge of the muon momentum scale and resolution, precisely determined from resonances decaying in two muons.
The aim of this thesis is to provide a validation of the muon momentum resolution at better than 5% enabling a measurement of the muon momentum scale at 0.1 permil level.

This thesis contains also a preliminary study on one of the CMS subdetectors, allowing to measure its material budget at a few percent level.