CiPo - Beamline

Spherical Grating Monochromator (SGM)

The beamline SGM monochromator covers the energy range 40 - 1000 eV, working in Padmore-type configuration and is equipped with a variable angle plane mirror and four different spherical gratings (G1 to G4), that cover the following energy ranges:

• G1 grating (1050 l/mm) from 440 to 1000 eV

• G2 grating (1050 l/mm) from 300 to 700 eV

• G3 grating (1050 l/mm) from 120 to 400 eV

• G4 grating (550 l/mm) from 40 to 140 eV

The photon flux avaiable on the sample, as well as the photon energy resolution, is crucial for the proper evaluation of the feasibility of a given experiment. In the following figures the photon energy band width togheter with the corresponding value of the photon flux is plotted as a function of the entrance and exit slits width. The data reported have been measured at 245 (Ar L2,3 absorption threshold) and 867 eV (Ne K absorption threshold) were resolution has been determined from the Gaussian brodening obtained with a fitting procedure performed using Voight functions while the photon flux was determined by using the double ion chamber.