Free-electron laser inverse-Compton interaction x-ray source

Free-electron lasers (FEL) and synchrotron sources of high brilliance x-rays have proven to be of tremendous value in basic and applied research. Inverse-Compton sources (ICS) can achieve brilliance matching the requirements of many applications pioneered at those FEL and synchrotron facilities---including phase contrast imaging, macromolecular x-ray crystallography, and x-ray microscopy---but with size, cost, and complexity compatible with a small laboratory. The free-electron laser inverse-Compton interaction compact x-ray source at the University of Hawaii at Manoa is a unique approach to an ICS which employs an FEL as the laser source. We have measured a total average flux of $3.0\ifmmode\times\else\texttimes\fi{}{10}^{5}\text{ }\text{ }\mathrm{photons}/\mathrm{second}$ with an average brilliance of $2.0\ifmmode\times\else\texttimes\fi{}{10}^{7}\text{ }\text{ }\mathrm{photons}/\mathrm{s}\text{ }{\mathrm{mm}}^{2}\text{ }{\mathrm{mrad}}^{2}$ 0.1% of bandwidth (BW) with a peak energy of 10.9 keV from the source. While these results are modest in comparison to the standards set by other IC sources, upgrades to the system have the potential to increase the total average flux to $9.2\ifmmode\times\else\texttimes\fi{}{10}^{11}\text{ }\text{ }\mathrm{photons}/\mathrm{second}$ with an average brilliance of $1.9\ifmmode\times\else\texttimes\fi{}{10}^{12}\text{ }\text{ }\mathrm{photons}/\mathrm{s}\text{ }{\mathrm{mm}}^{2}\text{ }{\mathrm{mrad}}^{2}$ 0.1% BW: comparing more favorably to other sources. We discuss the scientific program, the progress made in design and development, and the achievements of the source to date. We also outline future upgrades and integration needed to yield an enabling source for emerging high brilliance x-ray applications.