Hard X-ray nanofocusing at low-emittance synchrotron radiation sources

摘要

X-ray scanning microscopy relies on intensive nanobeams generated by imaginga highly brilliant synchrotron radiation source onto the sample with ananofocusing X-ray optic. Here, using a Gaussian model for the central coneof an undulator source, the nanobeam generated by refractive X-ray lenses ismodeled in terms of size, flux and coherence. The beam properties are expressedin terms of the emittances of the storage ring and the lateral sizes of the electronbeam. Optimal source parameters are calculated to obtain efficient anddiffraction-limited nanofocusing. With decreasing emittance, the usable fractionof the beam for diffraction-limited nanofocusing experiments can be increasedby more than two orders of magnitude compared with modern storage ringsources. For a diffraction-limited storage ring, nearly the whole beam can befocused, making these sources highly attractive for X-ray scanning microscopy