Institut de recherche sur les lois fondamentales de l'Univers

Using LHC Run1 data, the CMS experiment has set tight constraints on the total Higgs boson width, using off-shell production and decay to ZZ to four leptons, 4l, or two leptons plus two neutrinos, 2l2ν with l = e,μ. The study is based on the width-independent enhancement at large ZZ invariant mass expected for a SM Higgs boson. The 4l analysis makes use of the ZZ invariant mass distribution and of a matrix element likelihood discriminant to separate the ZZ components originating from gluon- and quark-initiated processes, while the 2l2ν analysis relies on the transverse mass distribution in jet categories.