The ultra-peripheral Pb+Pb collisions at √ sNN = 5.02 TeV recorded by the ATLAS experiment are used to study a rare light-by-light scattering process, γγ → γγ, allowed in quantum electrodynamics via a loop diagram. The report summarises recent light-by-light measurements conducted using a combination of 2015 and 2018 Pb+Pb data sets collected by the ATLAS experiment, corresponding to an integrated luminosity of 2.2 nb −1 . The light-by-light event candidates are required to consist of only two

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... hotons produced exclusively, each with transverse energy ET > 2.5 GeV, pseudorapidity |η| < 2.4, diphoton invariant mass mγγ > 5 GeV, and with diphoton transverse momentum pT γγ < 1 GeV and acoplanarity below 0.01. The diphoton invariant mass distribution is used to set limits on the production of axion-like particles. topics: light-by-light scattering, axion-like particles, ATLAS