The ultra-small-angle X-ray scattering instrument on UNICAT at the APS

A new ultra-small-angle X-ray scattering (USAXS) instrument has been commissioned as part of the UNICAT facility on the 33-ID line at the Advanced Photon Source. The instrument offers continuously-tunable optics for anomalous USAXS, 1000 times the throughput of earlier USAXS instruments1,2, high sensitivity and high resolution at low scattering vector, and a scattering vector range from below 0.00015 Aa-1 to above 0.5 Aa-1. Early results include USAXS from colloidal silica suspensions, and anomalous USAXS from rare-earth oxides in the presence of similarly-sized cavities in silicon nitride. The addition of side-reflection optics, in an optional configuration of this instrument, enables USAXS measurements of anisotropic as well as isotropic materials