The new Higgs particle in the H$\rightarrow$ZZ$^{*}\rightarrow$4l searches with the ATLAS detector

This poster presents updated results and measurements of the properties of the newly observed Higgs particle in the decay channel $H\rightarrow ZZ^{(*)}\rightarrow l^{+}l^{-}l'^{+}l'^{-}$, where $l,l'=e$ or $\mu$. The analysis is based on 4.6 fb$^{-1}$ and 20.7 fb$^{-1}$ of proton-proton collisions at 7 TeV and 8 TeV, respectively, recorded with the ATLAS detector at the LHC. An excess of events over background is observed at $m_{H} = 124.3$ GeV with a significance of 6.6 standard deviations. The mass is measured to be $m_{H} = 124.3^{+0.6}_{-0.5}$ (stat) $^{+0.5}_{-0.3}$ (syst) GeV and the signal strength at this mass is found to be $\mu = 1.7^{+0.5}_{-0.4}$. A spin-parity analysis is also performed: the Higgs-like boson is found to be compatible with the SM expectation of $0^{+}$, when compared pair-wise with $0^{-}$, $1^{+}$, $1^{-}$, $2^{+}$ and $2^{-}$.