Proposed NSLS X13B Microdiffraction Instrument

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Proposed NSLS X13B Microdiffraction
Instrument Source Optics James M.
Ablett National Synchrotron Light Source
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NSLS 2.8 GeV X-ray Storage Ring
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X13 Straight-Section
EPW
MGU
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NSLS 'Hard' X-Ray Sources
1st Harmonic
?MGU
? IVUN
X17 Wiggler
2nd Harmonic
X21 / X25 Wigglers
Log Brightness ( ph / sec / mm2 /mrad2 / 0.1
BW / 300 mA)
3rd Harmonic
X13 Wiggler
NSLS Bending Magnet
Photon Energy keV
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X13 Undulator Source
The Mini-Gap Undulator MGU the brightest
source of hard x-rays (E 3.7 keV 16 keV) at
the NSLS. MGU parameters 54
pole, 1.25 cm period At a gap of 3.3 mm ,
Magnetic field 0.92 Tesla and Deflection
Parameter, K1.07 Fundamental _at_ 3.7 keV,
4x1017 ph/sec/mm2/mrad2/0.1BW/300mA
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MGU Spectral Measurements (August 2002
Ablett,Berman)
MGU Brightness Magnetic Gap3.3 mm
MGU Tuning Curves
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8x1017
Calculated
6x1017
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Experiment
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4x1017
Brightness (ph/sec/mm2/mrad2/0.1BW/300mA)
LogBrightness (ph/sec/mm2/mrad2/0.1BW/300mA)
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2x1017
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0
12
14
16
10
8
6
4
2
2
6
10
14
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Photon Energy keV
Photon Energy keV
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Current X13B Beamline Status
monochromator
hutch
27
24
20
15
12
numbers (in meters )indicate distance from center
of X13 straight-section, where MGU is located.
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Specifications

• The X13B microdiffraction instrument will be
  modular and compactin design, which will make
  available a variety of x-ray optics forthe
  experimentalist.
• Focused X-ray Beams on the micron-length scale
  and below,
• together with low and high x-ray divergence will
  be available with these optics.These will be
  mounted on a motorized rails and will bereadily
  accessible.
• Pink Beam (Laue) and Monochromatic modes of
  operationwill be available.- Energy tunability
  will be accomplished through a 4 bounce
  monochromator.

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X13B Microdiffraction Instrument Layout
x-ray microfocusing optics
detector circle
four-bounce mono tank
vibration isolation table
diffractometer
vibration isolation table
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27
26
25
Distance from MGU source meters
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• Suite of Optics offered
• Pin Holes
• Capillaries
• KB Mirrors
• Zone Plates
• Planar Refractive Lenses (Current RD)

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• Key Features
• Achromatic - Energy independent focusing-pink
  beam and monochromatic modes
• Accurate Elliptical Figures Achievable (either by
  bending ormetal deposition ) Small Spot Sizes
• High Reflectivity at Grazing Incidence Angles

Kirkpatrick-Baez Elliptical Mirrors
Heavy metal
Polished spherical Silicon substrate
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X13B Microprobe
differentially-deposited elliptical KB optics
have been used at X13Bduring the past few years,
designed primarily for high-pressure x-ray
spectroscopy.
Vertical blade scan current derivative
Horizontal blade scan current derivative
9 microns FWHM
3 microns FWHM
blade position microns
blade position microns
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X13B Microprobe
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Calcium K? Fluorescence Mapping of Osteoarthritic
Bone
1.
3.7 mm
3.
1.
2.
2.
3.3 mm
3.
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Preliminary KB layout
25 m to MGU source
2cm
incident x-rays
focal position
3cm
10 cm
Expected Parameters 1 micro-radian figure
error Spot size 0.7 x 2 micron2 Divergence
1mrad (v) x 7 mrad(h) 8 keV, 6x109 ph/sec Gain
5x104
With Figure Error (1 micro-radian)
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X13B Microprobe RD Efforts -Planar Refractive
Lenses (K. Evans-Lutterodt, J.M. Ablett)
Intensity arb. Unit
Position mm
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Summary A state-of-the-art hard x-ray
microdiffraction instrumentis proposed for NSLS
mini-gap undulator beamline X13B.It will offer
a variety of x-ray microfocusing optics micron
scale spatial resolution and below high and
low divergence. Big-beam (unfocused )
mode. Pink Beam and Monochromatic Modes of
Operation. Simultaneous fluorescence and
diffraction information.