Search for high-mass diphoton resonances in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

TL;DR

This paper reports a search for high-mass diphoton resonances in proton-proton collisions at 8 TeV using the ATLAS detector, finding no deviation from the Standard Model and setting limits on Randall-Sundrum graviton masses.

Contribution

It provides the first experimental limits on Randall-Sundrum graviton masses at 8 TeV with the ATLAS detector.

Findings

No excess observed over Standard Model predictions.

Lower mass limits of 2.66 TeV and 1.41 TeV set for different couplings.

Results constrain models predicting high-mass diphoton resonances.

Abstract

This article describes a search for high-mass resonances decaying to a pair of photons using a sample of $20.3$ fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=8$ TeV recorded with the ATLAS detector at the Large Hadron Collider. The data are found to be in agreement with the Standard Model prediction, and limits are reported in the framework of the Randall-Sundrum model. This theory leads to the prediction of graviton states, the lightest of which could be observed at the Large Hadron Collider. A lower limit of $2.66$ ($1.41$) TeV at 95% confidence level is set on the mass of the lightest graviton for couplings of $k/\overline{M}_{\mathrm{Pl}} = 0.1$ ($0.01$).