Measurement of the Higgs boson mass from the $H\rightarrow \gamma\gamma$ and $H \rightarrow ZZ^{*} \rightarrow 4\ell$ channels with the ATLAS detector using 25 fb$^{-1}$ of $pp$ collision data

TL;DR

This paper presents an improved measurement of the Higgs boson mass using combined data from two decay channels with enhanced calibration techniques, resulting in a more precise value of approximately 125.36 GeV.

Contribution

The paper introduces an improved analysis method with better energy-scale calibration, leading to a more precise Higgs mass measurement from ATLAS data.

Findings

Higgs boson mass measured as 125.36 GeV

Enhanced calibration techniques improved measurement accuracy

Upper limits on Higgs total width derived

Abstract

An improved measurement of the mass of the Higgs boson is derived from a combined fit to the invariant mass spectra of the decay channels $H\rightarrow \gamma\gamma$ and $H \rightarrow ZZ^{*} \rightarrow 4\ell$. The analysis uses the $pp$ collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at center-of-mass energies of 7 TeV and 8 TeV, corresponding to an integrated luminosity of 25 fb$^{-1}$. The measured value of the Higgs boson mass is $m_H$ = 125.36 $\pm$ 0.37 (stat) $\pm$ 0.18 (syst) GeV. This result is based on improved energy-scale calibrations for photons, electrons, and muons as well as other analysis improvements, and supersedes the previous result from ATLAS. Upper limits on the total width of the Higgs boson are derived from fits to the invariant mass spectra of the $H\rightarrow \gamma\gamma$ and $H \rightarrow ZZ^{*} \rightarrow 4\ell$ decay channels.