First x-rays from a compact and tunable LINAC-based Compton scattering source

In this paper, we present the first measurements of x-rays produced with a compact, narrowband, and tunable inverse Compton scattering-based x-ray source, developed at Eindhoven University of Technology. A flux of 1.2 · 10³ photons per shot was measured, in agreement with simulations. Using a high-resolution spectral camera, we show that the photon energy can be tuned continuously from 5.8 keV to 10.7 keV with a bandwidth of 4%. The measured rms x-ray pulse length had an upper bound of 2.8 ps. Additionally, we show that the source allows full control over the x-ray polarization. The current average brilliance of the source is 10⁵ photons/(s × mrad² × mm² × 0.1% BW). By optimizing experimental parameters, implementing improvements to the setup and further conditioning of the accelerator structure, a brilliance of 10¹² photons/(s × mrad² × mm² × 0.1% BW) can be achieved, with photon energies up to 40 keV. Because the complete electron beamline fits on a single three m-sized optical table, it is suitable as an in-house X-ray source for laboratories, industrial production lines, museums, and hospitals.