Figure 4
Intensity (I) of the monochromatic synchrotron X-ray beam as a function of phosphor screen position (rsc) at θ = 48.8° and its derivative. The intensity was measured by a helium-filled ion chamber downstream of the screen as the screen was translated through the X-ray beam. The beam height, r, determined from the scan is shown by the vertical blue dotted line. [Inset] Double-crystal rocking curve. The second crystal pitch was set to the angle that maximizes I before measuring I(rsc). |