The Gamma Factory proposal for CERN

This contribution discusses the possibility of broadening the present CERN research programme by a new component making use of a novel concept of the light source. The proposed, Partially Stripped Ion beam driven, light source is the backbone of the Gamma Factory initiative. It could be realised at CERN by using the infrastructure of the already existing accelerators. It could push the intensity limits of the presently operating light-sources by at least 7 orders of magnitude, reaching the flux of the order of $10^{17}$ photons/s, in the particularly interesting $\gamma$-ray energy domain of \mbox{ $1 \le E_{photon} \le 400$ MeV.} This domain is out of reach for the FEL-based light sources based on sub-TeV energy-range electron beams. The unprecedented-intensity, energy-tuned, quasi-monochromatic gamma beams, together with the gamma-beams-driven secondary beams of polarised positrons, polarised muons, neutrinos, neutrons and radioactive ions would constitute the basic research tools of the proposed Gamma Factory. A broad spectrum of new opportunities, in a vast domain of uncharted fundamental and applied physics territories, could be opened by the Gamma Factory research programme.