Measurement of the Higgs boson mass in the gamma gamma and 4-lepton decay channels with the ATLAS detector

The mass of the Higgs boson is measured in the $H\to ZZ^*\to4\ell$ and in the $H\to\gamma\gamma$ decay channels with $36.1\text{ fb}^{−1}$ of proton-proton collision data from the Large Hadron Collider at a centre-of-mass energy of $13\text{ TeV}$ recorded by the ATLAS detector in 2015 and 2016. The measured value in the $H\to ZZ^*\to4\ell$ channel is $m_H =124.88\pm0.37\text{ GeV}$, while the measured value in the $H\to\gamma\gamma$ channel is $m_H=125.11\pm0.42\text{ GeV}$. The value of the Higgs boson mass obtained from a simultaneous fit to the invariant mass distributions in the two channels is $m_H=124.98\pm0.28\text{ GeV}$.