The Interaction of high brightness X-rays with clusters or bio-molecules

Moribayashi, Kengo

The analysis of three-dimensional structures of single bio-molecules has lately attracted considerable attention as an application of an X-ray free electron laser (XFEL) light. As the X-ray flux becomes larger, the better diffraction pattern is produced, however, the bio-molecules become more damaged. The damage, which appears as noise for this analysis, depend on the experimental parameters. We have shown the calculation results of the damage using various parameters such as wavelengths, pulses, X-ray fluxes. Since XFEL lights are focused to a spot size which is comparable with that of a bio-molecule in order to get high X-ray fluxes, it is not easy to irradiate the bio-molecule with the same X-ray flux for each shot. We also show our proposal for the measurement methods of the X-ray fluxes using the X-ray emission from hollow atoms and photo-electron spectra.