INSPIRE Morad Aaboud Georges Aad Brad Abbott Ovsat Abdinov Baptiste Abeloos Syed Haider Abidi Ossama AbouZeid Nicola Abraham Halina Abramowicz Henso Abreu 2025-11-17 CERN-LHC-ATLAS. Measurements of the cross section for $t\bar{t}\gamma$ production using the single lepton (e or mu) channel in proton-proton collisions at a centre-of-mass energy of 8 TeV with 20.2 fb^-1 of data collected in 2012. The fiducial region is defined as: - 1 electron or muon, 1 photon, at least 4 jets, at least 1 b-jet - ptLepton > 25 GeV, |etaLepton| < 2.5 - ptPhoton > 15 GeV, |etaPhoton| < 2.37 - ptJet > 25 GeV, |etaJet| < 2.5 - min(DeltaR(lepton,photon)) > 0.7 - min(DeltaR(jet,photon)) > 0.5 https://service.tib.eu/vdataset/inspirehep_9089c29a-06fb-4fa9-b603-5214d3f1e646 en INSPIRE-HEP Measurement of the $t\bar{t}\gamma$ production cross section in proton-proton collisions at $\sqrt{s} = 8$ TeV with the ATLAS detector dataset