A simple transfer-optics system for an extreme-ultraviolet synchrotron beamline

Radiometric experiments often require comparatively high intensities in the extreme ultraviolet, in the microwatt range. The monochromators that provide the high throughput needed for these experiments, though, do not always allow for end stations to be switched out easily. At the National Institute of Standards and Technology Synchrotron Ultraviolet Radiation Facility, the only beamline with sufficient extreme-ultraviolet power has a multi-ton endstation, which cannot be moved. We will describe a set of transfer optics that allow the photon beam to be collimated and deflected through a port on the downstream end of the large chamber. This allowed an absolute cryogenic radiometer to be attached, with the entrance cavity underfilled. We will describe ray-tracing results and offer preliminary results of the radiometer-based throughput of the system.