10m Off-Plane Eagle-type monochromator

1. Design concepts

This monochromator was designed for ultra high energy-resolution angle-resolved photoelectron spectroscopy and chemical dynamics experiments.The monochromator covers the energy range from 10 to 40 eV. The resolving power and throughput of the monochromator have been evaluated by using geometric ray tracing. The resolving power for the 10m-10m slit width is estimated to be higher than 100,000 for the 2400 l/mm gratings even with the slope error of 0.5rad. The flux at the end stations is estimated to be about 10¹² photons/s for the energy resolution of 100,000.

2. Optical layout

Energy resolution	〜100,000（N0=2400/mm) >100,000 (N0=3600/mm)
Photon Flux	1012 photons/s @E/E=100,000
Photon Spot size at the sample	under 0.1 mm x 0.1 mm