Poster

A measurement of the inclusive top quark-antiquark pair production cross section in proton proton collisions at a centre-of-mass energy of 13 TeV is used by the CMS experiment, together with the theoretical prediction at next-to-next-to-leading order, to determine the top quark mass and to extract a value of the strong coupling constant with different sets of parton distribution functions. Dilepton events are selected and the cross section is measured from a likelihood fit to the final state distributions. [...]

The Standard Model is one of the most successful theories at describing the strong, weak, and electromagnetic forces and the interactions between the elementary particles.The scalar boson discovered in 2012 at the Large Hadron Collider (LHC) might be consistent with the Higgs boson predicted by the Standard Model, thus validating the Higgs mechanism and therefore representing a further confirmation of this theoretical framework. However, the experimental data still leave plenty of room to determine whether or not an extension of the scalar sector is allowed.The LHC combination of the SM Higgs boson measurements at 7 and 8 TeV allows Higgs boson decays to BSM states with a rate of up to 34% at 95% confidence level.Presence of new physics within the context of the Two-Higgs-Double-Model and NMSSM theories allows the exotic decay of the Higgs boson into a pair of light pseudoscalars. [...]

A huge breakthrough in particle physics was achieved with the discovery of the Higgs boson in 2012, which was followed by precision measurements of its properties. So far, the discovered particle is found to be in good agreement with the predictions of the Standard Model, but there is still sizable room for theories with extended Higgs sectors, like Supersymmetry or general Two Higgs Doublet Models. [...]