13 IDE

 

Overview

Beamline 13IDE is an undulator-based, hard X-ray microprobe instrument with a particular emphasis on the development and application of X-ray microbeam analytical techniques to research problems in geochemistry, cosmochemistry and environemntal sciences.

The 13IDE X-ray microscopy beamline operates full time and is designed to access a relatively wide spectral range from 2.4 - 28 keV giving access to absorption edges from a wide range of elements of interest in geological, environmental, life, and materials sciences. The beamline configuration provides users access to a suite of complementary analytical methodologies with focused beam resolutions smaller than 1 µm. This includes X-ray fluorescence analysis and on-the-fly imaging at detection levels in the ppb range for given elements, focused X-ray fluorescence and absorption spectromicroscopy (both micro-XANES and micro-EXAFS), X-ray microdiffraction capabilities using high-speed area detectors, and the extension of all these methodologies to three dimensions as tomographic techniques.

The 13IDE source is a 3.6 cm period undulator optimized to provide a tunable energy range as low as 2.4 keV (sulfur K-edge). This device sits in a canted geometry with the 13IDC/D undulator. The 13IDE monochromator incorporates several relatively new design features. It uses a state-of-the-art direct-drive rotary stage with an air-bearing and ferro-fluid seal to provide a frictionless and ultra-smooth drive with no backlash, very high radial stiffness and low eccentricity and wobble.  This is a fixed-exit, cryo-cooled double crystal system and provides users access to either Si(111) and Si(311) crystals, depending on experimental requirement. Two horizontal mirrors downstream of the DCM are used to further separate the 13IDE monochomatic beam from the inboard beam of 13IDC/D.  These mirrors can focus the beam to create a secondary horizontal source (SHS) that illuminates a high stability precision slit in the 13IDB optical station.

The microprobe endstation includes new micro-focusing Kirkpatrick-Baez mirrors, capable of directly focusing the full vertical beam divergence and re-imaging the SHS, producing a tunable spot size.  This optical configuration allows efficient optimization of the final focus for either high flux or ultimate spatial resolution.

Beamline Staff

Matt Newville, newville@cars.uchicago.edu, 630.252.0431
Tony Lanzirotti, lanzirotti@uchicago.edu, 630.252.0433
Steve Sutton, sutton@cars.uchicago.edu, 630.252.0426

Supported Techniques

X-ray Absorption Fine Structure (µXAFS)

Microfocused XAFS to determine the speciation (local chemistry, quantitative determination of the local geometric structure around the absorbing atom) of the elements. Depending on concentrations, both µ-XANES and µ-EXAFS are possible as is oxidation state mapping of materials.

X-ray Fluorescence (µXRF)

Compositional analysis and mapping for elements with X-ray emission energies between ~ 2-28 keV. Multiple elements can be analyzed simultaneously. MDL highly dependent on sample, spectral overlaps, detector placement and absorbers, but ppb level detection is possible. Mapping utilizes continuous scanning approach with practical pixel times as low as 10-20 milliseconds. Non-destructive compositional mapping (diffusion, zonation), sector zoning in minerals, compositions of microparticles (soils, micrometeorites, aerosols), trace element distributions in cells, etc. Samples can be analyzed in air, in a moist or wet state, biological samples can be analyzed intact.

 

Cathodoluminescence images show zircons formed in granite melts, start from a core and add layers as granite and other phases crystallize from the melts. Does Ce concentration and valence vary with these growth zones ?  Nick Tailby, Dustin Trail, Rennselaer Polytechnical Institute

X-ray Diffraction (µXRD)

Microdiffraction analysis for mineral identification with spatial resolutions of <1 µm. Area detector readout at frame rates < 500 msec per frame possible, allowing for dynamic diffraction studies, diffraction mapping and tomogarphy, etc.

Fluorescence Microtomography (fCMT)

Element specific X-ray fluorescence tomography with micrometer spatial resolution. Our fCMT analysis employs a continuous scanning approach similar to that utilized in fast 2D mapping, with practical pixel times as low as 10-20 milliseconds. X-ray fluorescence (full EDS) from a sample is measured as it is translated (X) and rotated (theta) through the focused beam to generate a sinogram (top image shown below). In our implentation of the technique we use theta as the fast scan direction to improve stability. Tomographic slices of XRF intensity through the object are then reconstructed following the same methods utilized for absorption tomography.

Using fCMT methods researches can non-destructively examine trace element distributions in materials without the need for physical sectioning. The bottom image below of a reconstructed slice through a 150 micrometer diameter Arabidopsis seed (Punshon - Dartmouth College) shows the high resolution imaging possible at elemental concentrations below 100 ppm.

https://gsecars.sites.uchicago.edu/sites/gsecars.uchicago.edu/files/uploads/images/arabidopsis_fCMT.png

Detectors

  • Vortex ME4 silicon drift diode array detector
    • XIA Mercury and XMap digital X-ray processors supporting high-speed, on-the fly-mapping modes
  • Perkin Elmer XRD 1621 amorphous silicon area detector
  • MAR 165 CCD area detector
  • MAR 345 Image Plate area detector
  • ADC ion chambers
  • Microspec Wavelength Dispersive Detector

Additional Equipment

  • Peltier-cooled sample stage
  • Helium sample environments
  • Navitar Ultraviolet imaging illuminator
  • Prosilica visible-light CCD sample imaging system (~0.5 mm field of view)
  • Access to GSECARS laboratories including microscopy instrumentation, wet lab, fume hood, laminar-flow hood, glove box, sample prep areas.

Beamline Specifications

Source 3.5 cm undulator
Monochromator Type cryo DCM, Si(111), Si(311)
Energy Range 2.4-28 keV
resolution (deltaE/E) 1.1 x 10-4
flux (photons/sec) 6 x 1012 @ 10 keV

Science Highlights

Beamline Manual

Beamline Calendar