X-ray CCD calibration system using fluorescent lines

We have developed a CCD calibration system using fluorescent X-ray lines with energies ranging from 1.49 keV (Al Kα) to 11.2 keV (Se Kα). The absolute X-ray flux is calibrated by a gas proportional counter, while the emerging spectra are monitored by solid-state silicon detectors. In order to suppress contaminating X-rays in the fluorescence spectra, mechanical collimators were set in the X-ray beam line, high-purity targets for fluorescent lines were used, and band-pass filters were put on the X-ray beam line. As for the purity of the fluorescent X-rays, the typical purity achieved was ∼98%.