Study of H→WW reconstruction and coupling precision determination at Muon Collider

This thesis presents the study on the sensitivity achivable on the measurement of the cross section of the process mu mu -> H + X -> WW + X, 3 TeV c.o.m. energy, at the Muon Collider. The Muon Collider is a project of a future circular accelarator based on muon collision. It could reach energies of tens of TeV in the collision, allowing to investigate this region. The Muon Collider is particularly promising for the Higgs boson physics. The Higgs boson has a key role in the Standard Model and it has to be investigate deeply in order to fully understand its properties. In this optic it is crucial to measure the coupling constants to the other particle of the SM. This thesis is the first step to determine the precision achivable on the coupling constant gHWW. In this work a presentation of the Muon Collider project is given. First its physics potential is discussed, then the facility and the detector, together with the main issues to face. Then the simulation and reconstruction algortihm used to simulate the process are presented together with the estimation on the performance of the detector. The actual work done for this thesis concern the analysis of the process and the comparison with the physical backgrounds that may affect the measurement. The kinematic of the events has been study and the comparison between signal and background is shown. The purpose of this analysis is to understand which variables are useful to perform a signal to background discrimination. The actual discrimination is performed with a MultiVariate Analysis, in particular two Boosted Decision Trees were trained on the same signal sample but different backgrounds. Then the trained algorithm were applied to the sample in order to estimate the expected number of events at the Muon Collider. With these values the estimation of the sensitivity on the measurement of the cross section has been computed.