Electroweak corrections to e+e− → γγ as a luminosity process at FCC-ee

Abstract We consider large-angle two photon production in e + e − annihilation as a possible process to monitor the luminosity of a future e + e − circular collider (FCC-ee). We review and assess the status of the theoretical accuracy by performing a detailed phenomenological study of next-to-leading order electroweak corrections and leading logarithmic QED contributions due to multiple photon radiation. We also estimate the impact of photonic and fermion-loop corrections at next-to-next-to-leading order and the uncertainty induced by the hadronic contribution to the vacuum polarization. Possible perspectives to address the target theoretical accuracy are briefly discussed.