Simple Tools for Characterization of Synchrotron Beam Flux, Energy Resolution and Stability

Flux is a simple yet key indicator of overall beamline alignment. For many synchrotron measurements, the energy resolution and reproducibility are important characteristics as well. However, many beamlines do not have diffractometers capable of measuring the energy resolution in the experimental hutches. For absolute flux measurements, we have found that thickness calibrated Si photodiodes make very convenient, robust detectors capable of handling a wide flux range. For measuring the energy resolution, we have developed a simple, portable instrument analyzer applicable to any beamline with a scanning monochromator. This same instrument is capable of measuring the energy stability and reproducibility as well. We have used these to characterize many of the beamlines on the NSLS X-ray ring, and will present the methods and our experience to date to demonstrate their usefulness.