Quasi-monochromatic x-ray via laser Compton scattering for medical imaging

A quasi-monochromatic X-ray source has been developed via laser Compton scattering (LCS) between a high power laser and a high charge electron beam on the basis of an S-band compact electron linac at AIST. The LCS X-ray source consists of the 42 MeV electron linac with a laser photocathode rf gun and a Ti:Sapphire chirped pulse amplification (CPA) laser system. The LCS X-ray has been generated with arbitrary center energy of 10-40 keV with narrow bandwidth by changing electron energy and collision angle. The in-line phase-contrast (refraction contrast) imaging and the K-shell absorption edge imaging with biological specimens have been successfully demonstrated using the LCS X-ray for future medical applications. We describe details of the LCS X-ray source and these imaging results. (author)