Specifications

Photon source

source:	bending magnet, radius 5.5 m, magnetic field 1.2-1.45 T
polarisation:	~80% linear horizontal
energy range:	white light, critical energy 3.2 keV @ 2.0 GeV or 5.5 keV @ 2.4 GeV operation

Elettra storage ring parameters are available here.

Monochromator

Plane grating monochromator Bestec (SX-700 design) with a single grating

grating	energy range	resolving power	photon flux *
1200 lines/mm	22-1000 eV	7000 @     22 eV	1×108 ph/s
		6000 @     30 eV	3×108 ph/s
		5000 @     40 eV	1×109 ph/s
		4000 @     70 eV	5×109 ph/s
		3000 @   100 eV	1×1010 ph/s
		2000 @   300 eV	8×109 ph/s
		1000 @ 1000 eV	5×109 ph/s

* at 300 mA ring current, 2.0 GeV; 100/200 μm entrance/exit slit apertures. For more details see the next page.

Beam dimensions The vertical beam size (FWHM of the intensity profile) decreases with photon energy from 0.3 mm to 0.15 mm at 200 eV and stays below 0.15 mm at all higher photon energies. In the horizontal direction the beam size is approximately 0.4 mm at all photon energies at normal incidence (60° emission off normal). This value is double at usual spectra acquisition geometry, normal emission (60° incidence off normal), i.e. 0.8 mm.

Beam position stability In the whole tuning range the maximum vertical beam displacement is 0.1 mm. The horizontal displacement at normal incidence (60° emission off normal) is 0.5 mm. This value is double at usual spectra acquisition geometry, normal emission (60° incidence off normal), i.e. 1 mm.

Beam intensity profiles

Photon flux

The data were measured using a photodiode. Click on the graph to download the data in TXT format.

Mesh current normalization

How does the mesh current reflect the real photon flux? For quantitative analysis you can recalculate the mesh currents acquired during your experiment at each photon energy using the following sensitivities. Click on the graph to download the data in TXT format. 



 

Electron energy analyzer: Specs Phoibos 150

Hemispherical energy analyzer; 1D-delay line detector,
selectable slits and pass energy for energy resolution 25 to 1200 meV.
Iris apertures: 2.5-50 mm for angular acceptance ±{1-8)°.
Angle between the incident photon beam and the analyzer: 60° in the horizontal plane.
Acquisition software:

• SpecsLab2 for UPS/XPS, and
• KolXPD for NEXAFS, RPES, ARPES and XPD.

Sample stage

Sample manipulator with X, Y and Z linear movements, polar and azimuth rotations.

Sample heating
indirect resistive	Tmax = 1300 K
direct resistive through the sample	Tmax = 1300 K
Sample cooling
LN2 manipulator	Tmin = 100 K

The sample temperature is read by a K-type thermocouple (chromel/alumel), which is mounted on the rear side of the sample, or with an optical pyrometer.

For details see Sample mounting.

Experimental facilities

• laboratory X-ray source (Specs) Mg and Al K-alpha
• gas line with five precision leak valves
• e-beam evaporators (1 Oxford and 3 Tectra)
• two retractable stages for mounting e-beam evaporators without breaking vacuum
• Ar⁺ ion sputter gun (Varian)
• LEED (OCI)
• Quadrupole mass spectrometer Prisma (Pfeiffer)
• preparation chamber with Ar⁺ sputtering, gas line, quartz crystal microbalance and possible evaporators
• fast entry load lock

For details see End station.