The X-ray beamline of the Sychrotron Laboratory for Environmental Studies (Synchrotron Umwelt-Labor) combines diffraction, absorption and fluorescence measurements on environmentally-relevant materials with microfocusing capabilities.
 

Sources of pollution, path of contaminants, and the application of synchrotron radiation-based techniques via Molecular Environmental Science (MES) to environmental questions are the main tasks of this beamline.
 

The SUL X beamline is major part of the Synchrotron Laboratory for Environmental Studies supported by the German governments (BMBF and state Baden Württemberg) for dealing environmental questions with synchrotron radiation methods. Therefore this beamline is designed for combined measurements with a microfocusing capability.
 

Environmental samples are generally complex (e.g., contaminated soils, mining dump sediments), consisting of mixtures of mineral phases (amorphous, crystalline, with micrometer or nano-scale particle sizes), microbes, and in some cases vegetable material. Spatial distribution, speciation, and phase association of trace levels of contaminants are the basis for risk assessment and development of remediation strategies (e.g. arsenic speciation and distribution in groundwater related sediments). This problem is best addressed by synchrotron based techniques capable of providing spatial resolution in the micrometer range while allowing the combination of microfocused techniques (XRF, XAS, XRD, IR), as foreseen in the SUL concept.

 Detectors

 D1

 Fluorescence

7 element Si(Li) (Gresham, now e2v)

Resolution (averaged over all elements, optimum peaking time):
<140 eV (at 5.9 keV, 1000 cps)
<310 eV (at 5.9 keV, 100.000 cps)

Area per element 30 mm²

 D2

 Absorption

3 ionisation chamber (Oxford Instruments, IC-Plus type)

 Active lenght 5cm, Kapton windows 6 µm thick

 D3

 Diffraction

CCD detector (Photonic science)

Active area 80x120mm² (hor. x vert.)

Fiber optic 3.46:1 scaling down pixels 2048x2048, 16 bit dynamic through fusion mode

Readout time 3.3s – 21s
Vacuum compatible

 D4

 Selection of sample spots

Optical microscope (TSO Spezialoptik)

Resolution 2µm,

Transmitted and reflected light, Vacuum compatible

Sample stage

 Movement

 Range

 S1

 z stage

 105 mm

 S2

 x/y stage

 100mm / 40mm

 S3

 phi circle

 360°

 S4

 chi cradle

 10°

 S5

 theta circle

360°

 S6

 2 theta circle

  -160° to +15°