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SNS Experimental Facilities Oak RidgeX0000910/arb
Neutron Instruments for Materials Research
T.E. Mason
Experimental Facilities Division
Spallation Neutron SourceAcknowledgements: Doug Abernathy, John Ankner, Ken Herwig, Frank Klose, Jinkui Zhao, Xun-Li Wang
SNS Experimental Facilities Oak RidgeX0000910/arb
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A Brief Aside on What You Actually Measure:
98-6249 uc/rra
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Neutron Scattering Cross-Section
98-6250 uc/rra
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CW vs Pulsed Instrumentation
• In general continuous sources work with fixed wavelengths (, all t) and pulsed sources work with a wavelength band (t, all – using time and distance to determine velocities and hence wavelengths)
• If the useful wavelength band is dispersed over the full time between pulses then the pulsed instrument counts useful neutrons all of the time and the figure of merit is the peak flux
• If the full time between pulses is not useful then the figure of merit is reduced by the duty cycle
• For fixed wavelengths, counting continuously the integrated flux is the figure of merit
• Variations (e.g. pulsed instrument at CW source) can, and do exist
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Example – Reactor - SANS
As an example consider the static approximation in ahomogeneous system:
Fourier transform of scattering length density for an object
98-6259 uc/rra
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cAMP-Dependent Protein Kinase (PKA)Combining Neutrons with X-rays
•PKA catalyzes a variety of cellular activities, ranging from gene induction to color change in pigment cells.•PKA serves as the prototype for a class of enzymes which catalyzes protein phosphorylation, the major mechanism of cellular regulation.•The combination of neutron studies and x-ray structures of PKA subunits has provided insights into the quaternary structure of PKA, which is key to the understanding of PKA function.
SNS Experimental Facilities Oak RidgeX0000910/arb
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• RC with deuterated R-subunit
• PKA (R2C2) with deuterated R-subunits
• Free C and Truncated R with x-ray
Neutron Contrast Data of PKA and RC
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Momentum Resolution
98-6252 uc/trh
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Having Made Some Neutrons WeWant A Monochromatic Beam!
98-6253 uc/trh
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Pinhole SANS
• NIST/NSF 30 m SANS
• NG-3 cold neutron guide
• 20 MW reactor, hydrogen cold source
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NIST SANSCharacteristics and Performance
• Source: neutron guide (NG-3), 60 mm x 60 mm • Monochromator: mechanical velocity selector with variable speed and
pitch • Wavelength Range: 0.5 nm-2.0 nm • Wavelength Resolution: 9%-30% (FWHM) • Source-to-Sample Dist.: 4 m to 16 m in steps via insertion of neutron
guide sections • Sample-to-Detector Dist.: 1.3 m to 13 m • Collimation: circular pinhole collimation • Sample Size: 0 to 25 mm diam • Q-Range: 0.015 nm-1 to 6 nm-1 • Detector: 650 mm x 650 mm 3He position-sensitive proportional
counter (10mm resol.)
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• excitations characterized by ´´(Q,) a measure of absorption at (Q,).
• neutron scattering measures:S(Q,) ~ ´´(Q,) [n()+1].
• note: Q 0, recover uniform susceptibility.
• the proportionality constant involves magnetic moment direction and form factor.
Neutron Scattering and Spin Fluctuations
B ( , )Q
neutroninduces
transi tion
),(2
1),(
d
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o(Q,) for Metals
• Excitations are electron-hole pairs
• Lindhard susceptibility:
• As T 0 states near F dominate
• Note: NMR relaxation rate:
),(~
1
0,1
Q
fTT
o
B p q p
p q ppN
f f
i( , )
( ) ( )
( )Q
2 2
( , )Q
k
h-
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Normal State Energy Dependence
• As the frequency is increased the peaks become less well defined.
• The response is qualitatively quite similar to that of the spin density wave system Cr, above TN.
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Example – Reactor –Triple Axis
• RITA (Re-Invented Triple Axis) at Risø, DR-3 Denmark
• 10 MW reactor, supercritical hydrogen cold source
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Having Made Some Neutrons WeWant A Monochromatic Beam!
98-6254 uc/trh
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For Inelastic Scattering You AlsoNeed Energy Analysis
98-6256 uc/rra
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Crystal Monochromator (continued)
98-6255 uc/trh
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Triple-Axis Spectrometer Resolution
• There are analytical methods for calculating the resolution (Cooper + Nathans, Nielsen + Bjerrum-Møller, Popovici)
• These are obtained from the program RESCAL forcollimation 60'– 60'– 60' – 60'30' PG002 monochromator and analyzer10' sample mosaicEf = 5meV ( = 4.04 Å)h = 0 q = 1 Å-1
98-6258 uc/rra
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Incident Beam Optics
• Supermirror guide in front of the monochromator increases flux• Sapphire filter reduces gamma and fast neutron background and
protects guide• Velocity selector in front of monochromator remove higher order
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Effect of the Guide
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Secondary Spectrometer
• Area detector and analyser crystal array permits flexible focussing
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SPINS at NIST
• A similar (on the back end) instrument is SPINS at NIST
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Time-of-Flight Inelastic Instruments
• Two basic types – direct geometry – fixed Ei (e.g. HET chopper)
– Indirect geometry – fixed Ef (e.g. IRIS backscattering)
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Chopper Spectrometers
• Operate in the thermal to epithermal energy range – 5 meV < Ei < 1000 meV
• Use fast, magnetic bearing Fermi choppers to select E i
• Maximal Q range with continuous coverage to large scattering angles– Need room at least on one side for scattering chamber
Consider two choppers should be placed on the bottom upstream moderator at end positions - BL9 & BL18 at SNS
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Target Layout
X = 5 m
X = 6.5 m
BL18
BL17
BL9
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Geometric constraints
X m
2
LiLf
BL18: X = 5 m m = 35°
For 2 >125° & Lf = 2.5 m , Li =13.0 m
For 2 = 60° & Lf = 6.0 m , Li =13.1 m
BL9: X = 6.5 m m = 35°
For 2 >125° & Lf = 2.5 m , Li =15.7 m
For 2 = 60° & Lf = 6.0 m , Li =15.8 m
m fm i 2sinLsinL X
Accessible regions in Lf lie below a straight line in (Li,Lf) plane
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Flux on sample at 200meV - 5% elastic resolution
Optimum flux not accessible for any L3
BL18 Constrained 5% elastic resolution
0.0E+00
1.0E+05
2.0E+05
3.0E+05
4.0E+05
5.0E+05
6.0E+05
7.0E+05
0 10 20 30 40 50 60
Source-Sample distance (m)
Flu
x o
n s
amp
le (
n/c
m2/s
)
1000meV
200meV
50meV
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Flux on sample at 200meV - 1% elastic resolution
Can optimize flux for a given L3 that is not too large
BL18 1% elastic resolution
0.0E+00
1.0E+04
2.0E+04
3.0E+04
4.0E+04
5.0E+04
6.0E+04
7.0E+04
8.0E+04
9.0E+04
1.0E+05
0 10 20 30 40
Source-Sample distance (m)
Flu
x o
n s
amp
le (
n/c
m2/s
)
L3 = 6m
L3 = 5m
L3 = 4m
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Proposed two spectrometer layout
T0
E0
Pit Area
Sample
Beamstop
Detectors
BL17 - “high resolution”
BL18 - “high flux”
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Instrument parameters
Spectrometer High Flux High Resolution
Ambient H2O decoupled poisoned 18BU 100mm(H) x 120mm(V)Moderator anddimensionsAngle 13.75 (possible 27.5 ) 0 (possible 13.75 )GeometrySource-chopper (L1)Chopper-sample (L2)Sample-detector (L3)
12.0m1.5m2.5m
15.5m2m6m
ChoppersT0 horizontal axisT0 vertical axisE0 (Fermi) vertical axis
Mechanical 60 Hz @ 7.0m(Magnetic 300 Hz @ 7.5m)Magnetic 600 Hz @ 12.0m
Mechanical 60 Hz @ 9.0mMagnetic 300 Hz @ 10.0mMagnetic 600 Hz @ 15.5m
GuideTypeLength
Tapered supermirror 3c
~7mTapered supermirror 3c
~11m
Apertures and collimatorsAfter E0 (Fermi) chopper
2 VariableSoller collimator
3 VariableSoller collimator
Max. sample size 50mm(H) x 75mm(V) 50mm(H) x 75mm(V)
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Instrument parameters
Spectrometer High Flux High Resolution
Scattering/samplechamberRadius sample-detectorHeightVacuum at sampleVacuum flightpathCollimationShielding, innerShielding, outer
2.5m2.5m< 10-6 torr< 10-2 torrOscillating radial collimatorB4C, 50m2
~0.5 m (TBD) thick, 100m2
6m6m< 10-6 torr< 10-2 torrOscillating radial collimatorB4C, 150m2
~0.5 m (TBD) thick, 250m2
Linear PSDsNumberTypeDiameterLengthResolutionTotal pixelsAngular range, horizontal
Vertical, low bank Vertical, high bankLow bank solid angle/areaHigh bank solid angle/areaTotal area
5403He 10 atm25mm900mm25mm50,400-45 to -3 , 3 -150
30
2.15 sr / 13.5 m2
13.5 m2
12003He 10 atm25mm900mm25mm50,400-30 to -2 , 2 -30 (low), 30 -60 (high) 30 100.70 sr / 26 m20.12 sr / 4 m230 m2
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Resolution and flux calculations
0.0E+00
1.0E+05
2.0E+05
3.0E+05
4.0E+05
5.0E+05
6.0E+05
7.0E+05
8.0E+05
0 1 2 3 4 5
Elastic resolution (%)
Flu
x o
n s
amp
le (
n/c
m2/s
)
1000meV High Flux 50meV High Flux1000meV High Res 50meV High Res
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Resolution and flux calculations
1.0E+03
1.0E+04
1.0E+05
1.0E+06
1 10 100 1000 10000
Energy (meV)
Flu
x o
n s
amp
le (
n/c
m2 /s
)
High Flux 3.0%
High Res 1.4%
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Q- space accessible with proposed spectrometers
Q (Å-1)0.01 0.1 1 10 100
(
meV
)
10-3
10-2
10-1
100
101
102
103
104
d (Å)0.1110100
2eV crystal analyzer
10-100eV multichopper1% high-resolution chopper3% high-flux chopper
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Comparison to current chopper spectrometers
Instrument L1 (m) L2 (m) L3 (m) Moderator,Tilt
% energyresolution
AngularRange(Hor)
DetectorSolidAngle (sr)
LRMECSANL
6.2 0.8 2.5 CH4 2.5 – 7 % 3 - 120 0.3
HRMECSANL
12.7 1.1 4 CH4 2 – 4 % 3 - 140 0.5
HETISIS
10 1.8 2.5/4 H2O, 27 2 – 4 %3 - 30110 - 135
0.1
MARIISIS
10 1.7 4 CH4, 13 1 – 3 % 3 - 132 0.1
MAPSISIS
10 2 6 H2O, 14 1 – 3 % 3 - 60 0.45
PHAROSLANSCE
18 2 4 H2O , 15 1.5 - 3% 1 - 140 0.65
PHOENIX ISIS(HET upgrade)
12 1.8 2.5 H2O, 27 2 – 4 % 3 - 150 3.1
SNSHigh flux
12 1.5 2.5 H2O, 14 2 – 4 % 3 - 150 2.15
SNSHigh res.
15.5 2 6 H2O, 0 1 – 1.5 % 2 - 60 0.82
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High Resolution Backscattering Spectrometer
• Performance gains over comparable reactor backscattering instruments >100 (depending on bandwidth needed)
• High-Q option (with Si 311) 500x IN13 and 18x IRIS (with 3 times Q range and better resolution!)
• Crystal analyzer (Si) with 84 m incident flight path
• Achieves 2.2 eV resolution at the elastic position with
250 eV bandwidth
• Can operate up to 18 meV energy transfer with 10 eV resolution
• Unprecedented capabilities
2000-03452/arb
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Instrument Resolution and Q- Range
(meV)
0 5 10 15
Q (
Å-1
)
0
1
2
3
4
(meV)
0 5 10 15
f
whm
( e
V)
0
5
10
15
20
25
• Elastic Resolution 2.2 eV (fwhm)
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supermirror funnel
detector for top analyzer
detector forbottom analyzer
beam stop
top analyzerbottom analyzer
evacuatedsample chamber
scattering vessel
Scattering Chamber
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Guide Design
• 84 m total flight path moderator face to sample
• Curved guide– radius of curvature 4.325 km
– 10 cm horizontal x 12 cm vertical
– Natural Ni (outer radius horizontal needs higher index)
– begins 1 m from moderator face
• Supermirror funnel, ends 30 cm from sample– horizontal, 3 x c for Ni, 10 cm to 3 cm over 5 m
– vertical, 4 x c for Ni, 12 cm to 3 cm over 6 m
• Gains– 1200; = 6.3 Å
– 400; = 3.2 Å
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39
Shutter and Core Insert Regionsfor the Standard Shutters
Distance from Moderator (m)
0 1 2 3 4 5 6 7
Rel
ativ
e G
ain
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
= 6.3 Å
= 15 Å
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Major Spectrometer Components
• Source/Moderator decoupled, supercritical poisoned H2, TU
• Incident flight path - 84 m moderator face to sample position
• Chopper System - 3 bandwidth/frame overlap choppers
• Sample - dimensions 3 x 3 cm2
• Analyzer crystals, Bragg angle = 88 deg– Si (111): = 6.267 Å, 2.9 ster, 26 m2, d/d ~ 3.5 10-4
– Si (311): = 3.273 Å, 1.45 ster, 13 m2, d/d ~ 4.0 10-4
• Final flight path - 3 m sample-analyzer, 2.5 m analyzer-detector
• Detectors– Backscattering for diffraction
– ~ 7040 cm2 PSD 1 x 1 cm2 spatial resolution
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Melittin in Alkanethiol/Phospholipid Hybrid Bilayer Membranes - NIST
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Melittin in Alkanethiol/Phospholipid Hybrid Bilayer Membranes - NIST
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NG1 Reflectometer: Polarized Beam - NIST
0.0 0.1 0.2 0.3 0.4 0.510-10
10-9
10-8
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
Neutron Reflectivity and 2-Layer Fitof 10nm. SiO2 Film on Si
Log (
Ref
lect
ivit
y)
Q[A-1] 0 5 10 15 20 25
0
1x10-4
2x10-4
3x10-4
4x10-4
SiO2
Si
Nb
[n
m -2 ]
Depth [nm]
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MBE Chamber for In-situ Neutron Scattering on the NG1 Reflectometer
UHV Techniques Protective Environment
Epitaxial Thin Film Growth
Gas Loading (e.g. H)
Sputter Etching of Surface Material
RHEED Analysis
Mass Spectrometry
Scattering TechniquesSpecular Reflectometry
Off-Specular Scattering
Grazing Angle Diffraction
High Angle Diffraction
SANS
PhenomenaAdsorption / Desorption
Diffusion
Segregation
Morphology
Crystallography
Magnetism
Superconductivity
Joe Dura NIST-NCR
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Reflectometry
• In addition to providing a unique probe for magnetic surfaces and multi-layers polarized neutrons permit direct inversion to obtain the scattering length density profile - no phase problem– a magnetic reference layer buried in the substrate can have
magnetization wrt neutron polarization varied
– for a weak absorbtion probe (valid for the neutron) three known references lead to unique solution
– drawback is the price paid in sensitivity for polarized beam
• Off-specular reflection for in-plane structure
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SNS Reflectometers
• 2 reflectometers sharing a single beamport
• Requires new multi-channel shutters in the target station
• Allows for both vertical sample (magnetism) and horizontal sample (liquids) studies
• Novel beam bender optics allows multiplexing and reduces background
• Reflectivities <10-9, 10-50 times faster than any existing instrument
2000-03451/arb
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Instrument features
• Views coupled 20-K H2 moderator from beamline 4TD
• Shares beamline with magnetism reflectometer
• Multi-channel beam bender eliminates all < 1.5 Å
• Three bandwidth choppers allow clean operation in 0.5-4.5, 5-9, or 9.5-13.5 Å wavelength frames
• Tapered guide delivers angular bandwidth that can be sampled by slits at 0 < < 7° relative to the horizontal
• 1-mm2-resolution PSD permits study of off-specular and grazing-incident small-angle scattering
• For liquid samples 0 < Q < 0.5 Å-1 is accessible; by tilting a solid surface, 0 < Q < 1.0 Å-1 (Rmin ~ 4×10-10)
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Schematic
SourceMicroguide
BenderTaperedGuide Slits
Detector
14.5 m
Bandwidth Choppers
• Bender/tapered guide combination eliminates source line-of-sight
• Tapered guide delivers angular bandwidth that allows multiple angles of incidence
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Microguide bender4c
Ni
• Bender acts as high-pass wavelength filter
• Multiple channels n transmit higher flux
[Left]: Phase-space acceptance at 5-channel bender exit for 9-Å neutrons after 0-5 bounces (red-green). [Right]: Integrated acceptance for n-channel benders.
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Reflectometer beam benders
Bender insidewide shutterdeflects the beamdownward to a4.75° angle ontosample surface.
Sample
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Tapered guide
Tapered guide provides angular bandwidth for liquid measurement. Slits select sample incident angle about = 4.75° centerline.
12 cm
1.75 cm
4cNi
Contours representratio of actual to maximum optical acceptance (X / Xmax)at tapered guide exit.
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Slits
= 2.06°; = 0.0014;X / Xmax = 0.89; mavg = 3.3
= 4.75°; = 0.0061;X / Xmax = 0.86; mavg = 1.3
Slit settings off the = 4.75° centerline exhibit higher averagenumber of bounces mavg. Judicious selection of incident angle ensures optimal acceptance X.
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Liquids reflectometer
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1.E-111.E-101.E-091.E-081.E-071.E-061.E-051.E-041.E-031.E-021.E-01
1.E+00
0.00 0.25 0.50 0.75 1.00
Q (Å-1)
R
0.20° 1
0.30° 2
0.50° 4
0.75° 7
1.20° 12
1.90° 21
3.00° 33
4.25° 53
5.75° 103
8.00° 436
11.25° 6436
15.00° 15436
Performance comparison
POSY-II
MURRADAM,NG-1
SURF
SNS reflectometers will accumulate specular reflectivity data 10-50 times faster than the best existing instruments. ImprovedQmax will yield near-atomic-scale layer-thickness sensitivity.
Simulated data from 10-ÅSiO2 layer atop Si. SNS-Lutilizes 12 incident anglesi to measure Qmax > 0.9 Å-1
in t < 5 hours (18,000 s).Arrows indicate reflectivities measured in 12-24 hours(40-80,000 s) by existing instruments.
i ti (s)
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SNS Powder Diffractometer
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Detector Array
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Characteristics of Major Components
• Source/Moderator - decoupled poisoned ambient water
t0 = 10 s at = 1 Å
• Incident Flight Path - 60 m moderator-sample distance
curved supermirror guide with 3cNi coating, 1.5 cm wide x 3 cm tall
~ 8 m moderator-guide distance adjustable 9 m guide-sample distance
• Chopper System - To and 2 bandwidth/frame-overlap choppers
• Collimators - variable aperture for incident beaminside scattering chamber - oscillating radial collimator
outside scattering chamber - fixed radial collimators
• Detectors - type TBD 10° – 170° in-plane, ±30° out-of-plane coverage (±45° at 90°) 40 mm tall x 5 mm wide pixel size~ 6 ster solid angle coverage, ~ 47 m2 area1 – 6 m variable distance from sample
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Narrow Bandwidth Concept
• Previous TOF diffractometers used detector "banks" at a few angles, along with a broad wavelength range to produce a limited number of data sets of intensity vs. wavelength.
• A new idea put forward by Paolo Radaelli proposes the use of wide angular coverage and full 60 Hz operation to collect a single data set of intensity vs. angle and time-of-flight. These spectra would then be combined "appropriately" after-the-fact to produce a single histogram with intensity vs. d-spacing.
• This new data collection/analysis concept can be applied to any detector geometry. However, it appears optimally suited to a continuous detector locus, with this locus chosen to optimize the resolution as a function of d-spacing.
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D-spacing-Lambda Space Coverage
0 1 2 3 4 5 6 7 80
5
10
15
20
25
low-resolution
high-resolution
fra
me
-3
fra
me
-4
fra
me
-5
fra
me
-1
fra
me
-22 = 20°
2 = 30°
2 = 60°
2 = 90°2 = 150°
narrow bandwidth discrete banks
d-s
pac
ing
(Å
)
incident lambda (Å)
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GEM Powder Diffractometer at ISIS
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Detector Locus
Lscat
= A + Bcot
8 m
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D-spacing Coverage of POW-GEN3
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D-spacing Coverage of POW-GEN3
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Instrument Resolution Function
180 160 140 120 100 80 60 40 20 00.000
0.005
0.010
0.015
0.020
0.025
GEM-ISIS HRPD-ISIS POW-GEN3
Res
olut
ion
(fw
hm
d/d)
Scattering Angle (°)
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Neutron Source
0 1 2 3 4 5 60
2
4
6
8
10
12
14
16
2MW-SNS POW-GEN3 0.15MW-ISIS GEM
x F
lux
at S
ampl
e (M
n.cm
-2.s
-1)
Wavelength (Å)
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Neutron Source
0 1 2 3 4 5 6 7 8 9 100
10
20
30
40
50
60
70
80
2MW-SNS POW-GEN3 0.15MW-ISIS GEM
4 x F
lux
at S
ampl
e (M
n.cm
-2.s
-1)
Wavelength (Å)
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Simulated Diffraction Experiment
1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.400
2000
4000
6000
8000
10000
120000.5 gram Y-Al-Fe-O Garnet 60s (d/d = 0.0002)
POW-GEN3 GEM 90° Bank
coun
ts
d-spacing (Å)
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Simulated Diffraction Experiment
0.45 0.50 0.550
200
400
600
800
10000.5 gram Y-Al-Fe-O Garnet 60s (d/d = 0.0002)
POW-GEN3 x10 GEM 155° Bank
coun
ts
d-spacing (Å)
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Another Variation on Powder Diffraction: Residual Strain
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SNS SANS
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0 1 2 5 8 1 0 1 4d istan ce fro mm od era tor [m ]
Next Bea m lin
e
2.5m
Schematic Layout
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Bender System: guide-bender-guide
tw
RRtw
RRR
La
LR
Ra
xR
LxRxLL
2 and ;
2);tan()
(cos(
;)sin(
)sin( ; with )1)(
2tan(
212
1
21
22
1
212
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Bender System: Performance
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Choppers
0
2
4
6
8
10
12
14
16
18
0 20 40 60 80
Time [ms]
Dis
tan
ce
fro
m s
ou
rce
[m
]
1.03Å
4.65Å
T1
T2
T3
0
2
4
6
8
10
12
14
16
18
0 20 40 60 80
Time [ms]
Dis
tan
ce
fro
m s
ou
rce
[m
]
3.72Å
7.3Å
T1
T2
T3
SNS Experimental Facilities Oak RidgeX0000910/arb
79
Soller Collimators: Configuration
14 m(S a m p le)
18 m(D etector )
10 m 12 m
G uid e
SNS Experimental Facilities Oak RidgeX0000910/arb
80
Soller Collimators: Direct Beam
2c m 1c m 4c m
16m 16m
14 m(S a m p le)
18 m(D etector )
10 m 12 m
G uid e
SNS Experimental Facilities Oak RidgeX0000910/arb
81
Soller Collimators: Resolution and Flux
8m pinhole1cm sample
1cm beam spot,2cm sample
1cm beamspot,
1cm sample
0 1 2 3 4F lux : 16m pinhole
0%
100%
200%
300%
0.1 1 10two-th ita [°]
Q/Q
Soller: source=1.75cm ,sam ple=1cm . Beam size ondetector =1cmSoller: source=3.5cm ,sam ple=2cm . Beam size ondetector =1cmpinhole: source-sam ple=8m ,detector-sam ple=8m
pinhole: source-sam ple=16m ,detector-sam ple=16m
SNS Experimental Facilities Oak RidgeX0000910/arb
82
Low Angle Detector
Needed:1 x 1 m2
5mm resolution 1Å103 n/s/pixel4 x 107 n/s/detector low background
Needed:1 x 1 m2
5mm resolution 1Å103 n/s/pixel4 x 107 n/s/detector low background
Available (3He):1 x 1 m2
7 mm resolution 5Å104 n/s/wire106 n/s/detectorLow background
Available (3He):1 x 1 m2
7 mm resolution 5Å104 n/s/wire106 n/s/detectorLow background
1.25 2.5 bar (concave structure)counting efficiencyresolutioncounting rate
5mm wire spacing.
1.25 2.5 bar (concave structure)counting efficiencyresolutioncounting rate
5mm wire spacing.D etek to r
B alas tkam m er ( H e)4
M em bran
K a lo tte(D ruckausgle ich)
SNS Experimental Facilities Oak RidgeX0000910/arb
83
High Angle Detectors
20 x Standard 3He PSD
SNS Experimental Facilities Oak RidgeX0000910/arb
84
Performance: Flux at the End of the Bender-Sytem
SNS Experimental Facilities Oak RidgeX0000910/arb
85
Performance: Flux at Sample (14m)
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
0 2 4 6 8 10 12 14
Wavelength [A]
Flu
xa
ts
amp
le[n
/s/c
m2
/A]
1 m co llim ation , S u m = 9.14 E 82 m co llim ation , S u m = 4.79 E 83 m co llim ation , S u m = 2.29 E 84 m co llim ation , S u m = 1.3E 8
`
SNS Experimental Facilities Oak RidgeX0000910/arb
86
Performance: Flux vs. Collimation
Max. counting rate: 700n/s/pixel at 1m collimation 100n/s/pixel at 4m collimation
1.E+06
1.E+07
1.E+08
1.E+09
0 5 10
Collimation length [m]
Inte
grat
ed F
lux
[n/c
m2/
s]
integrated flux between7.33 and 10.99ÅHFIR,9.16Å, 10%
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
0 5 10
Collimation length [m]
Inte
grat
ed F
lux
[n/c
m2/
s]
integrated flux between3.66 and 7.33ÅHFIR,5.49Å, 10%
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
0 5 10
Collimation length [m]
Inte
grat
ed F
lux
[n/c
m2/
s]
integrated flux between 1and 4.66ÅHFIR,2.83Å, 10%
SNS Experimental Facilities Oak RidgeX0000910/arb
87
Q-Coverage
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0 5 10Q [Å -1]
d
(Q)/
d
[cm
-1]
D 2O (coh + inc)
H 2O (coh on ly)
protein
lipid(solvent)
Qmin= 0.004 Å-1 (Pinhole) = 0.001 Å-1 (Soller)
Qmax = 12Å-1 (1st Frame)= 3.3Å-1 (2nd Frame)= 1.6Å-1 (3rd Frame)
3rd Frame 1st Frame
Huey HuangRice University
SNS Experimental Facilities Oak RidgeX0000910/arb
88
Performance (low angle detector)
Extend-Q SANS
30-Meter SANS, NIST (Q=0.0015-0.6 Å-1)
(=15%) Qmin [Å-1]
Simulated flux
×106 [n/s]
Qmin [Å-1] Measured flux(*)
×106 [n/s] 0.001-0.15(s) 0.8, 3 (2cm) 0.0015-0.3(s) 7, 25(2cm) 0.0015-0.013(10Å) 0.09 0.004-0.13 14 0.002-0.019(7.5) 0.26 0.006-0.25 120 0.003-0.025 0.85 0.008-0.35 170 0.0064-0.04 6.38 0.01-0.5 360 0.016-0.1 30.9 0.02-0.8 820
SNS Experimental Facilities Oak RidgeX0000910/arb
89
Performance
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
1.E+11
0.001 0.01 0.1 1 10
Q [1/Å]
Coun
tRat
epe
rSo
lidA
ngle
[arb
unit]
1st Fram e, 0-4m collim ations2nd F ram e, 0-4m collim ations3rd F ram e, 0-4m collim ationsSoller, 1-3 fram esSoller,2cm x2cm sam pleH igh Angle Detec tors, 1-3 fram esNIST 30m S ANSD11/ILL
SNS Experimental Facilities Oak RidgeX0000910/arb
90
100Å Polystyrene (0.625%) in 5mm D2O, 15sec simulation
1.E -02
1.E -01
1.E+00
1.E+01
1.E+02
1.E+03
0 0.05 0.1 0.15 0.2 0.25 0.3
Q [1/Å]
I(Q
)[n
pix
el-1
s-1
]Theore tica lExtended-Q SAN S, 2nd fram e, 4m sam ple-to-detector3 X H FIR SANS, 6Å,10% , 4m sam ple-to -detector
100ÅGuide Detector
4m 4m
Performance : MC simulation