Gamma Factory for CERN initiative : progress report

The Gamma Factory (GF) initiative proposes to use partially stripped ion (PSI) beams as drivers of a new type of high-intensity and high-energy (0.1–400 MeV) photon source. As part of the ongoing Physics Beyond Collider studies, initial beam tests were carried out in 2017 and 2018 at the SPS and LHC with partially stripped xenon and lead beams. This contribution discusses the results of these tests and the preparations for the next GF R&D step: the proof-of-principle experiment at the SPS to study interaction of PSI beams with the laser light.