Figure 7
The water-cooled HHL chopper. Panel (a) shows a cross-sectional view, in which the X-ray beam impinges on the chopper perpendicular to the rotor surface. An air bearing provides frictionless rotational motion while water flows down the shaft along the center of rotation (red arrow). Panels (b) and (c) show the rotor and a close-up view of the slot configuration. The entire chopper can be translated horizontally to choose different slot widths. The location of the beam port behind the slotted disc in panel (c) is at the 3 o'clock position of panel (a). |