Comment by gnufx

Indeed. The first dedicated light -- for various values of "light" -- source[1] repurposed the tunnel and various bits and techniques from the particle physics accelerator it replaced, and on which parasitic "light" measurements were made previously. See also [2].

1. https://en.wikipedia.org/wiki/Synchrotron_Radiation_Source

2. https://www.ukri.org/publications/new-light-on-science-socio...