Searches for BSM physics in dilepton, multilepton, and lepton+MET final states at CMS

We describe various searches for signs of physics beyond the Standard Model in proton-proton collisions collected by CMS in 2012 or 2015. These datasets correspond respectively to around 20 fb$^{-1}$ of integrated luminosity at a center of mass energy ($\sqrt{s}$) of 8 TeV and around 2.5 fb$^{-1}$ at $\sqrt{s}=$ 13 TeV. The analyses presented here focus on final states with one or several leptons and possibly missing transverse energy, for which the background from Standard Model processes is reduced, and primarily targets the production of new particles with masses in the TeV range. The performances of the lepton reconstruction and identification at large transverse momenta play a crucial role in these searches and are discussed. No evidence of new physics is seen and upper limits level are set at the 95$\%$ confidence on the cross section of new phenomena leading to the various final states considered. The results are interpreted as lower limits on the mass of new particles predicted by a variety of models, leading to exclusion well above 1 TeV in many cases, and surpassing the previous results at $\sqrt{s}=$ 8 TeV for all the analyses performed with the 2015 dataset.