  The aim of the proposed CERN Gamma Factory is to produce $\sim 10^{17}$
photons per second with energies up to 400 MeV. The photon beam intensity is
expected to be a factor of $\mathcal{O}(10^7)$ larger than that of the
presently available photon beams in the MeV energy range. In this work, we
explore its potential to probe physics beyond the Standard Model. In
particular, we discuss searches for axion like particles (ALPs) with dominant
couplings to photons and consider various production scenarios - fixed target,
photon-photon collision, and conversion by a magnetic field and detection
schemes - via decay to photons or back-conversion. We find that the Gamma
Factory in a fixed target mode can probe ALPs with mass $m_a \lesssim
\mathcal{O}(100\,\mathrm{MeV})$ and decay constants larger than $10^7$ GeV,
improving by an order of magnitude the discovery potential of previous beam
dump experiments.
