I would like to start the Australian Science Case for an Australian XFEL to be built in Australia.
One design I think would provide incredible opportunities in science, as well as being feasible in cost, is a compact (lab-scale) XFEL based on the ASU CXFEL: The Arizona State University's Compact XFEL, being led by Prof. William Graves. https://biodesign.asu.edu/cxfel/.
The CXFEL is being built in two stages with the first stage completed (first light in late 2022), based on inverse Compton scattering. By "Compact" I mean ~ 30 m from electron gun to detector. Stage 1 is called the Compact X-ray Light Source (CXLS). The CXLS offers undulator like radiation at a fraction of the cost of a whole synchrotron beamline.
The CXFEL design builds on the CXLS and turns it into an XFEL based on nanopatterning the relativistic electron beam, then manipulating it in phase space (emittance exchange) to flip the transverse spatial modulation into a longitudinally spaced electron bunch: the microbunches needed to coherently emit, maximising radiation output in the (laser) undulator. Related papers can be found here: https://inspirehep.net/literature/1690439
The purpose-built building that houses the CXFEL and CXLS labs at Arizona State remind me of the Monash Electron Microscopy centre (though it doesn't have glass walls), to give you some sense of the investment needed.
Early 2024 update:
Currently I'm organising a Advanced X-ray Source Focus Session at the AIP Congress 2024 in December in Melbourne, to gather interested parties to discuss the needs, potential applications, interest and relevant expertise (and what capacity building this will require) for a future X-ray source. I am leaning towards an XFEL, but this discussion will also include sources like the CXLS and other Inverse Compton scattering sources or other sources people are interested in. It's not clear whether discussions around a national facility (like the CXFEL) and compact truly table-top sized novel sources for advanced medical imaging research and applications would attract very different groups of people, but that's part of the motivation for this Focus Session.
Name TBC. Australian & New Zealand Extreme X-ray Source? ANZEXS ? EXANZ ? Extreme X-rays for Australia and NZ? I like EXANZ.
Current related sources under construction:
Europe: three Extreme Light Infrastructure facilities are under construction. Some info about their beamlines: https://www.eli-beams.eu/
These include fs laser pulses for medical use too.
USA: The US National Science Foundation has funded 3 mid-scale extreme light facilities: CXFEL at Arizona State University, NeXUS at Ohio State, and ZEUS at the University of Michigan.