Study of the decays of the Higgs boson to boson pairs at Run-II with the ATLAS experiment

The Higgs boson plays an important role in the Standard Model:it provides mass to the elementary particles through the electroweak spontaneoussymmetry breaking (EWSB). Discovered in 2012 by the ATLAS and CMS Collab-orations, today the Higgs boson is a very powerful tool to test the validity of SMtheory at the TeV scale. The Higgs boson can be produced at proton-proton collid-ers, such as LHC, in different ways and many decay channels are predicted by theStandard Model. At ATLAS Run-2, this particle is widely studied mainly throughits decays in vectors boson pairs ($\mathit{H\rightarrow ZZ^*, H\rightarrow WW^* and H\rightarrow \gamma \gamma }$). In thiscontext, the latest results, obtained using the dataset collected by the ATLAS ex-periment during 2015 and 2016 at a center-of-mass energy of 13 TeV, are presented.Experimental techniques and estimates of the main backgrounds will be discussedin detail.