• dark matter candidates
• MC study
• new physics
• Precision Proton Spectrometer
• search
• toy MC

This thesis work deals with the search for the associate production of a Z boson and a new massive particle X with two forward protons in the PPS, the forward proton spectrometer of the CMS experiment. The search is model independent and performed in a mass range of the X particle between 800-1600 GeV. The expectations on the signal hypothesis are based on a simple toy Monte-Carlo (MC) generator, that I contributed to develop. The effects of the PPS miscalibration on a possible signal are presented as well, and represent the first time that such studies are performed within the PPS collaboration. Finally, an analysis of the main backgrounds of the search is performed and several selection cuts are presented. These are expected to enhance the significance of an excess in the hypothesis that the X particle is fully invisible to the central detector.