Beamline Description
The photon flux
The photon flux on the sample has been measured with a calibrated silicon diode AXUV IRD-100. The photon flux as a function of energy has been measured for two limit cases: Maximum flux and Higher order rejection. For energies greater than 100 eV (G1200 grazing incidence channel), the maximum flux condition is obtained following the deviation angle curve that maximizes the diode current intensity, while Higher order rejection corresponds to the deviation angle that maximizes the photon flux, but with higher orders contribution less than 1%. The photon flux at CK edge has a drastic drop caused by optics contamination. Below 100 eV, the curves ‘High spectral purity’ are obtained inserting the appropriate filters. The beamline is in fact also equipped with a carousel for choosing the appropriate filter and window for delivering high purity radiation.
Experimental Photon Flux on the sample
(E=2.4 GeV, Elettra current 100 mA, Vertical slits = 100 um)
Monochromator working curves used to optimize flux or high purity radiation
The windows and filters for high purity radiation
Filter/Window (Thickness)
Energy
Pyrex window
2.7-4
Fused silica
3.9-7.8
LiF window
5.6-11.2
In filter (0.1 μm)*
12-17
Sn filter (0.15 μm)*
15-24
Al filter (0.2 μm)*
36.25-72.5
Si filter (0.5 μm)*
50-100
Ag filter(0.6 μm)
200-400
Ti filter (0.7 um)*
225-450
(*: filters supported by Ni mesh with nominal transmittance of 0.86)
range (eV)
Wavelength
range (nm)
Filter ID for macro
B270 window
(1 mm)
2.7-4
310-459
1
(4 mm) (Refo Valve)
310-459
15
SiO2 window(1 mm)
159-318
2
(0.5 mm)
110-221
3
72-103
5
51-83
6
Mg filter (0.3 μm)*
25-50
24.8-51
7
17.1-34.2
8
12.4-24.8
9
B filter (0.5 μm)*
90-180
6.8-13.8
10
Parylene filter
(1 μm)
140-280
4.4-8.8
14
3.1-6.2
12
2.7-5.4
11
Cr filter (0.5 μm)
400-570
2.1-3.1
4
Cu filter(0.7 μm)
500-930
1.3-2.48
13
Nominal transmittance of available windows and filters
