Constant deviation monochromator for the range 100 Å≤λ≤1000 Å.

A grazing incidence constant deviation monochromator with a spherical concave grating was fabricated for use with undulator radiation. It has a simple scanning mechanism with fixed entrance and exit slits, as well as fixed directions of incident and exit beams. It has been installed into an undulator beamline at IMS. Synchrotron radiation from a bending section also can be introduced into the monochromator by using premirrors. The energy resolution of the monochromator is better than 70 meV at the photon energy of 94 eV with 10-μm slits, when the bending magnet synchrotron radiation is used. The spot size of the zeroth-order light is 1.5 ( v ) × 2.0 (h) mm² at the distance of 1.85 m behind a postmirror. The photon flux of the undulator radiation behind the exit slit is approximately 1 × 10[sup 12] photons/s at the peak, when both the entrance and exit slits are 100 μm (δE = 0.08 eV) and the stored current is 50 mA. [ABSTRACT FROM AUTHOR]