MEX technical summary

MEX-1

MEX-2

Beam energy

Monochromatic, 3.4 – 13.8 keV

Monochromatic 1.7– 3.2 keV

Number of Endstations

2

1

Source

 Bending magnet (BM12-1)

Bending magnet (BM12-1)

Optics

Mirror 1 (M1)

Vertical collimation

•  Fixed, flat Si substrate

• Cylindrically bent

• Bounce up (4.75 mrad)

• Exchangeable Si, Ni and Rh stripes

Front end mirror (M1)

Vertical collimation

• Fixed sagittal cylinder

• Horizontal bounce (15 mrad)

• Cr stripe

Double crystal monochromator

• Two pairs of Si<111>:

  • Crystal azimuth 0° and 30°

• dE/E ≈ 1.4 ×10^-4

• Vertical bounce up

Mirror 2 (M2)

Horizontal collimating

• Fixed cylinder

• Horizontal bounce (15 mrad)

• Cr stripe

Mirror 2 (M2)

Vertical and horizontal focussing

• Cylindrical + flat Si substrate

• Elliptically bent

• Bounce down (4.75 mrad)

• Exchangeable B₄C and Rh stripes

Double crystal monochromator

• Si<111>, dE/E ≈ 1.4 ×10^-4

• InSb<111>, dE/E ≈ 3 ×10^-4

• Crystal azimuth 0°

• Vertical bounce

 Endstations

XAFS Station

• EXAFS/XANES

• 3.4 – 13.8 keV

• Transmission and florescence (4 element Si EDS detector)

• Sample temperature 10 – 300 K (in He_(g))

• Non-ambient sample environments

• Beam size

  • 0.15 – 0.5 mm vertical

  • 0.1 – 7 mm horizontal

• Flux 3 x 10¹¹ ph sec^-1

“Low energy station”

• EXAFS/XANES

• 1.7 – 3.2 keV

• Transmission, drain current and fluorescence (4 el. Si SDD)

• HERFD-XAS: >Dispersive refocusing Rowland geometry

>Single cylindrically bent, Si<111> Johann analyser

• Beam size 0.1 – 3 x 0.1 – 5 mm²

• Flux: Si<111> 5 x 10¹⁰ ph sec^-1

InSb<111> 1 x 10¹¹ ph sec^-1

• Sample in He_(g) or vacuum

• Sample temperature 10 – 500K

Microprobe station (coming in 2025)

• µEXAFS/µXANES

• 2.1 – 13.6 keV

• 3 el. Si SDD

• 2-moment KB mirror system

• Exchangeable Si and Rh stripes

• Beam size: 3 – >20 µm

• Flux 10⁸ ph^-1 sec^-1 µm²

• Sample in He_(g)

• Sample temperature 80 – 500K

• Scan range < 80 × 80 mm

Crystal spectrometer

• Moved to XAS Beamline!

• HERFD-XAS: > 0.5 m Johann-type crystal analyser

• 5x spherically bent crystals. See here for further information on crystal cuts and accessible emission lines​​​​​​