Danny Winterbottom (ICL)

Measurements of Higgs boson properties by the CMS Collaboration

Abstract: The standard model (SM) Higgs sector predicts exactly one physical Higgs boson with CP-even couplings to the SM particles. This year marks the 10th anniversary of the discovery of a boson with a mass of around 125 GeV that appears to fulfil this prediction. However, many extended Higgs sectors can also accommodate such a particle. These models usually predict modified couplings and/or properties of the 125 GeV boson, which can be directly tested by precision measurements at the LHC. Deviations in the observed Higgs boson properties, including its natural width and CP nature, would be clear signals of new physics and could help address several shortcomings of the SM, such as its inability to explain the observed excess of matter over antimatter in the universe. The Higgs boson mass on the other hand is the only free parameter of the SM Higgs sector, and therefore a precise determination is essential to extract bounds on the Higgs couplings from cross-section measurements. In this seminar, I will discuss the latest measurements of each of these properties by the CMS Collaboration.