Abstract:
This talk presents the search for new resonances in the diphoton final state with the ATLAS experiment at the Large Hadron Collider (LHC). The analyses are based on proton-proton collision data collected by the ATLAS detector at a centre-of-mass energy of $\sqrt{s}=13$~TeV. In the diphoton invariant mass range from 65 to 110 GeV, search is performed for a spin-0 resonance, as predicted by many models that include extensions to the Higgs sector, using 80~$fb^{-1}$ data collected in 2015, 2016 and 2017. In the higher invariant mass region above 160 GeV, two kinds of signal are searched for using 139~$fb^{-1}$ data collected in 2015-2018: a spin-0 resonant state, and a spin-2 graviton excitation state predicted by the Randall-Sundrum model with one warped extra dimension. For both low-mass and high-mass searches, no significant excess is observed with respect to the Standard Model expectation. Upper limits are placed on the production cross-section times branching ratio to two photons as a function of the resonance mass. In addition, a study on the photon-specific energy calibration systematic uncertainty from electromagnetic shower leakage mis-modeling in the ATLAS electromagnetic calorimeter is also presented.
Zoom link: https://cern.zoom.us/j/67380320623?pwd=UGFBak1rRmwzckkwNG9ObTJsZzNsUT09
ID：673 8032 0623
code：436257