Measurements of the properties of the Higgs-like boson in the two photon decay channel with the ATLAS detector using 25 $\mathrm{fb}^{-1}$ of proton-proton collision data

Measurements of the mass and couplings of the Higgs-like boson in the two photon decay channel with the ATLAS detector at the LHC are presented. The proton-proton collision datasets used correspond to integrated luminosities of 4.8 $\mathrm{fb}^{-1}$ collected at $\sqrt{s}$ = 7 TeV and 20.7 $\mathrm{fb}^{-1}$ collected at $\sqrt{s}$ = 8 TeV. The updated measurements benefit from an increased data sample and an improved analysis. The measured value of the mass of the Higgs-like boson is $126.8 \pm 0.2 (\mathrm{stat}) \pm 0.7 (\mathrm{syst})$ GeV and the fitted number of signal events is found to be $1.65 \pm 0.24 (\mathrm{stat}) ^{+0.25}_{-0.18} (\mathrm{syst})$ times the value predicted by the Standard Model. Measurements of the signal strengths in different production processes and a fiducial cross section for the observed particle are also presented.