2024

Study of 𝘡 → 𝑙𝑙𝛾 decays at √s = 8 TeV with the ATLAS detector

This paper presents a study of 𝘡 → 𝑙𝑙𝛾 decays with the ATLAS detector at the Large Hadron Collider. The analysis uses a proton–proton data sample corresponding to an integrated luminosity of 20.2 fb⁻¹ collected at a centre-of-mass energy √s = 8 TeV. Integrated fiducial cross-sections together with normalised differential fiducial cross-sections, sensitive to the kinematics of final-state QED radiation, are obtained. The results are found to be in agreement with state-of-the-art predictions for final-state QED radiation. First measurements of 𝘡 → 𝑙𝑙𝛾 decays are also reported.