Observation of $t\bar{t}{\hat{I}}^3{\hat{I}}^3$ production at $\sqrt{s}=$13 TeV with the ATLAS detector

ATLAS Collaboration

This paper presents the first observation of top-quark pair production in association with two photons ($t\bar{t}{\hat{I}}^3{\hat{I}}^3$). The measurement is performed in the single-lepton decay cha…