Optical design and performance of the X25 hybrid wiggler beam line at the National Synchrotron Light Source

The X25 beam line at the National Synchrotron Light Source (NSLS) began full‐power commissioning in 1990. It extracts radiation from a 27 pole hybrid wiggler, which produces up to 1.8 kW of total power with a peak horizontal density of 450 W/mrad and critical energy of 4.6 keV. The design and performance of the beam line optics are described, in particular, the cooling of the first monochromator crystal.