Performance and characterization of aluminum x-ray lenses

Abstract

We report on the characterization and the performance of a set of paraboloidal aluminum x-ray lenses. 28 lenses (with a design radius of 170μm) were stacked and tested at the Materials Research Collaborative Access Team (MRCAT) insertion device beamline (10-ID) at the Advanced Photon Source at Argonne National Laboratory. Knife-edge scans were performed at various distances downstream of the stack to determine the focal distance. The estimated focal distance is 2.72m horizontally and 2.63m vertically, with a focal size (FWHM) of approximately 12.5μm in both directions. The photon flux density measured at 2.68m from the stack was 30.5 times that of the unfocused beam. Several lenses of various radii were individually characterized at a bending magnet beamline (BM05) at the European Synchrotron Radiation Facility using x-ray speckle vector tracking metrology. Results indicate that lens profiles deviate from an ideal paraboloidal shape by about 1μm rms.