This paper reports recent tests performed on the Bonse-Hart-type ultra-small angle X-ray scattering (USAXS) instrument at the Advanced Photon Source with higher-order reflection optics Si (440) instead of Si (220) and with X-ray energies greater than 21.0 keV. Our results demonstrate the feasibility of high-energy operation with narrower crystal reflectivity curves, which provides access to a scattering vector range from ≈ 2 × 10-5 to 1.8 Å-1 and up to 12 decades in the associated sample dependent scattering intensity range. The corresponding size range of the scattering features spans about 5 decades from less than 1 Å to ≈ 30 μm. These tests have indicated that mechanical upgrades are required to ensure the alignment capability and operational stability of this instrument for general user operations due to the tighter angular-resolution constraints of the higher-order crystal optics. These upgrades are now underway.
Citation: Journal of Applied Crystallography
Pub Type: Journals
Bonse-Hart ultra-small-angle X-ray scattering instrument, USAXS, Ultra-high SAXS resolution