Conclusions

Abstract

With the analysis of the coupling structure of the observed particle the search for the SM Higgs boson concluded for the CMS collaboration with the complete and exhaustive analysis of the full LHC run-1 dataset of the years 2011 and 2012. The final lap of this hunt had started with the commissioning of the LHC and the experiments in 2010 and the establishment of all known SM processes with tremendous reliability and precision. The hot phase started in 2011 with the first limits based on the searches in the main SM Higgs boson decay channels, $H\rightarrow \gamma \gamma$, $H\rightarrow ZZ$, $H\rightarrow WW$, $H\rightarrow \tau \tau$ and $H\rightarrow b \bar{b}$, in a range of $100<m_{H}<1000$ GeV. These days were characterized by a vibrant atmosphere of tension and excitement at CERN, which reached its first and highest peak on 4 July 2012 with the announcement of the discovery of a new particle in both large scale main purpose experiments at the LHC, ATLAS and CMS, in the combination of the bosonic decay channels at ATLAS and all main decay channels at CMS. This discovery was based on roughly half of the dataset that has been collected across the whole timespan of the years 2011 and 2012. It was driven by the bosonic decay channels, while the two main fermionic decay channels, $H\rightarrow \tau \tau$ and $H\rightarrow b\bar{b}$, were just around the corner to reach the sensitivity for observing the new particle. The discovery was followed by the evidence that the new particle indeed couples to fermions end of 2013 and a complete analysis of its spin, $CP$ properties and coupling structure, as far as possible with the available dataset.