MAX4, a 3 GeV light source with a flexible injector

The MAX4 ring is intended to be the future user facility at MAXlab. The high-brilliance 3 GeV storage ring, equipped with small gap, short period superconducting undulators, demonstrates a high mean brilliance over a wide photon energy spectrum. The ring itself is defined from the routine operation of the small gap insertion devices, which is reflected in the small aperture of the ring magnets. The development of future light sources, like the free electron laser and energy recovery systems, opens up new challenging possibilities to create high brilliance, short pulse radiation. This development is today far from being mature, a strong development of new ideas and techniques will most probably take place during the next decade(s). The MAX4 full-energy injector is constructed to incorporate these future developments. The proposed 3 GeV energy recovery race-track microtron will open up the possibility of topping up injection and to deliver Fourier transform limited spontaneous as well as coherent radiation up to the hard X-ray spectral region