Beamline Optics

Source (ESRF/ ID15A):

7 pole asymmetric wiggler

critical energy: 44.1keV

gap: 20.3mm

low energy cutoff at 40keV (by 4mm Al absorbers)

Beam properties:

Energy range: 50 - 120 keV

Energy resolution: 2·10^-3 .. 10^-5

Beam size: vertical 3 µm - 5 mm

Beam size: horizontal 20 µm - 10 mm

Focal length: 1 - 8 meters

Beam divergence: 30 µrad (after focusing)

flux: ∼ 5·10¹⁰ ph/sec at 70 keV (focused)

Optical Components:

Double crystal monochromator

Standard setup with two asymmetrically cut and bent Si(111) crystals in fixed exit geometry



1st (white beam) monochromator (M1)




2nd monochromator (M2)







offset: 50mm

assymetry cut: 37.76°

bending radius: 60m

Liquid scattering geometry

New concept for liquid spectrometer using 4 bent crystals to deflect the incident beam.

complete optics





The tilt monochromator allows to vary the incident angle while keeping the beam position on the sample fixed.

Tilt monochromator principle



Tilt monochromator station

Focusing:

-Compound Refractive Lense (2D focusing) with an adjustable number of lenses N=0..300





-Bent multilayer (1D focusing)



-Fast shutter and beam cleaning slits