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CHESS East
F3 Station
The F3 station is a versatile bend-magnet station
that can accommodate a variety of experimental capabilities. It has a
double-crystal Si (111) as a standard monochromator with a sagittal focusing
second crystal which focuses about 3 mrad of bending magnet radiation,
tunable from 6 to 18 keV. A vertically focusing mirror will be
installed downstream of the monochromator to provide a doubly-focused beam
at the station. Alternatively, four sets of unfocused multilayers can
be used as the monochromator, providing wide-bandpass radiation at 0.22%,
2%, 5%, or 10% with a tunable energy range of 5-11 keV. Considerable
efforts are currently devoted to novel optics development and
characterization at the station, especially in the area of high-resolution
and other special multilayers.
Two standard experimental setups are available at F3.
The first is a conventional small 4-circle diffractometer with an analyzer
th-2th stage for high resolution diffraction, x-ray reflectivity, and
diffuse scattering studies. Typical samples include semiconductor
and organic thin-films, small molecule crystals, nanofabricated or
self-organized lateral quantum dot structures. This setup also is
suitable for x-ray topographic studies, x-ray imaging, and small /
wide-angle scattering experiments. An x-ray fluorescence detector
can be set up to monitor fluorescence signals from the specimen for
resonant / anomalous diffraction, surface scattering, and x-ray standing
wave experiments. An x-ray polarimeter (shared with C-line) may be
mounted on the 2-th arm for polarization analysis of a diffracted beam.
The second setup at F3 is a special 5-circle kappa
diffractometer with a Quantum-4 CCD area detector (or Fuji image plates)
and a complete shutter-collimator-video camera setup for oscillation
crystallography data collection. The special 5-circle diffractometer
along with a special version of CCD control software is designed for
direct phase measurements of Bragg reflections in oscillation
crystallography using a reference-beam diffraction phasing technique.
The diffractometer geometry can also be arranged as a standard oscillation
camera with a single horizontal rotation axis, controlled through standard
MacCHESS oscillation software. Other experiments using this setup
include studies of disorders in protein crystals, radiation damage control
in protein crystallography, and SAD phasing with intrinsic sulfur
anomalous signals at <6 keV.
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F3 station summary |
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Source: |
e+s,
Hard bend magnet HB7E, 6 mrad (horizontal) into F3 |
Source size:
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FWHM (horizontal) = 3.63 mm, FWHM (vertical) = 1.06 mm |
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Distance to
source: |
21.6 m to center of hutch |
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Be windows: |
0.040 inch to F3 hutch |
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Cave slit sizes: |
0 to 100 mm (horizontal), 0 to 5mm (vertical) |
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Monochromators: |
Double-bounce downward, offset 25 - 110mm |
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Crystals |
Sag. Focus. |
Energy
(keV) |
 |
 |
/2 |
/3 |
|
Si
(111) |
Yes |
6-20 |
1.3 |
0.008 |
0.093 |
|
Si
(111) |
No |
6-20 |
1.3 |
0.008 |
0.093 |
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2%
Multilayers |
No |
6-11 |
200 |
|
|
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0.22% Multilayers |
No |
6-11 |
22 |
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| |
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Monochromatic Mirrors: |
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Type |
Length |
Vertical Focus |
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E* c(keV-mrad) |
Rh
coated Si
(available soon) |
600mm |
Yes |
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67.0 |
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Typical Experiments: |
|
Type |
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Equipment Setup |
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High Res. Scattering
EXAFS
Radiography
Near-edge diffraction
Oscillation Crystallography
Reference-beam diffraction |
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Small Huber 6-circle
diffractometer Optical Table
Special k-diffractometer
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Update:
2006-09-21
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