Physics studies to define the CMS muon detector upgrade for High-Luminosity LHC

In view of the High-Luminosity phase of LHC, the CMS detec- tor will undergo a major upgrade, the Phase-II Upgrade (2024), consequent to the Phase-I Upgrade (2019). To improve redundancy and extend the coverage to high pseudo-rapidity regions, the muon system will be equipped with new Micro Pat- tern Gaseous detectors. To understand the effects of the muon detector Phase-II Upgrade, Monte Carlo simulations samples reproducing different detector scenarios have been produced. Then the detector response to the Higgs reconstruction has been studied, analyzing Higgs boson decaying into four muons events. The results of the comparison between the different configurations are reported, together with considerations regarding the improvement given by the geometrical extension of the muon system to the Higgs reconstruction.