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XTOD Diagnostics for Commissioning the LCLS*
XTOD Diagnostics for Commissioning the LCLS*
January 19-20, 2003LCLS Undulator Diagnostics and Commissioning
WorkshopRichard M. Bionta
January 19-20, 2003LCLS Undulator Diagnostics and Commissioning
WorkshopRichard M. Bionta
*This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-
Eng-48 and by Stanford University, Stanford Linear Accelerator Center under contract No. DE-AC03-76SF00515.
*This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-
Eng-48 and by Stanford University, Stanford Linear Accelerator Center under contract No. DE-AC03-76SF00515.
R. M. Bionta
WBS 1.5 X-Ray Transport, Optics, & WBS 1.5 X-Ray Transport, Optics, & Diagnostics (XTOD) Diagnostics (XTOD)
• Provides unobstructed vacuum path from end of undulator to end of FEH
LCLS X-Ray Beam
Tunnel
NEH - NearExperimental
Hall
• Flux densities in NEH will be the highest available
• Flux densities in FEH will be similar to synchrotron facilities
FEEFront End Enclosure
FEH - FarExperimental
Hall
R. M. Bionta
X-ray Transport, Optics, and Diagnostics X-ray Transport, Optics, and Diagnostics LayoutLayout
Front End Enclosure Diagnostics Slits Attenuators
Low EnergyOrder SortingMirror
FEL Measurements & Experiments:CompressionSpectraCoherencePulse Length
MonochrometerPulse-Split & DelayDiagnostics
ExperimentsOpticsStructual BioNano-scaleFemtochem
FEENEH FEH
Tunnel
Experiments:OpticsWarm Dense MatterAtomic Physics
Each 13 m long hutch has two vacuum tanks for experimental and facility hardware
R. M. Bionta
FEL beam power levelsFEL beam power levels
LL
DG
DGPsat3
16.1
28
1
3/2
c
KFK wp
ncr ee
p
24
fDG
DG
LL
1
1
3
1
f
a1d
a2a3
a4
a5a6
a7a8
a9a10
d
a11 a12
a13d
a14 a15
a16d
a17 a18
a19
LLRayleigh
DG
d
1
FELf
nDGL 41
EL
Photonw
eDG
14
Saturated power
FEL r parameter Plasma frequency
Gain length parameterization
Correct definition of h parameters
R. M. Bionta
Spatial-temporal shapeSpatial-temporal shape
eee zRyxi
zw
yxzzkti
zzikw
kwptzyxE22
2
122
020
20 20
)(2,,,
kw
zzkwzw
0
0
2240 4
kzz
zzkwzR
0
0
2240 4
4
1
ew 20
LRayleighExitzz 0
wPp sat
2
000
2
4
fst 2330FEL can be modeled as a Gaussian beam in optics
Phase curvature function
Gaussian width Gaussian waist
Origin is one Rayleigh length in front of undulator exit
Amplitude is given in terms of saturated power level
R. M. Bionta
LCLS Fundamental Electric Field LCLS Fundamental Electric Field and Dose Equationsand Dose Equations
0
22
20
22
02
1
020
20)(
)(2),,,( zzR
yxki
zzw
yx
zzkitti ceezzikw
kwpeetzyxE
202
02
2202
0 ww
zzzzw
0
240
00 4
1
zz
kwzzzzRc
2
22
2
1
22e
yx
e
electronelectron e
N
Rexit Lzz 0
ew 20
2
0
22
2
20
2022 zzw
yx
bunchbunch ezzw
wpE
2
0
22
2
,, zzw
yx
peakphoton ezAzyx
20
2
zzw
NzA photon
peak
photon
bunchsatphoton E
PN
photoionphotonphotonEDose
Gaussian Electric Field:
With origin waist PhaseCurvature
Waist at origin matches electron distribution gives
Electric field intensity x duration
Matches photon distribution with
Peak photon density
Dose
R. M. Bionta
FEL parameters at absorber FEL parameters at absorber exit, z = 65 metersexit, z = 65 meters
Minimum Maximum UnitsElectron kinetic energy, T 4.54 14.35 GeV
Fundamental wavelength, 1.50 0.15 nm
Fundamental photon energy, Ephoton 0.828 8.271 KeV
FEL saturated power, Psat 11.0 9.6 Gwatt
Bunch duration, bunch 233 233 fsec
Position from undulator center, z 65.00 65.00 mFundamental transverse FWHM 232.7 86.7 micron
Peak photon density, Apeak 315 199 photons/nm2
And at other locations:
FEL Photon Energy: 0.828 KeV 8.27 KeVZ FWHM Apeak FWHM Apeak
m micron /nm2 micron /nm2
Undulator Exit 50.0 79 2351 67 290Slit 59.9 176 532 77 225Absorber Center 63.7 217 356 81 205Mirror Tank 82.0 414 99 102 134Crystal 84.4 440 88 105 128Experimental Area 100 610 46 124 93
R. M. Bionta
Ginger provides complex Ginger provides complex Electric Field envelope at Electric Field envelope at undulator exitundulator exit
23768 8N
Data in the form of
radial distributionsof complex numbersrepresenting theenvelope of the Electric Field at theundulator exit. tit
c
nt
16n
Samples are separated in time by
wavelengths.
Time between samples is
Ni ..1R, mm0 150
Each radial distribution has
47NRradial points.
Electric Field Envelope Power Density vs timeat R = 0
wa
tts
/cm
2
R. M. Bionta
ToolsTools for manipulating GINGER for manipulating GINGER outputoutput
0 150
GINGER output:
Tables of electric field valuesat undulator exitat different times
Time Domain
Frequency Domain
TemporalTransform
SpatialTransform
00
1.94
150-150Transverse position, microns
x 1015 wattsc m2
Power Density
0
1.94
x 1015 wattsc m2
0 6Time, femtoseconds
42
Power Density
0w0w0-400/fs
1.73
x 1017 wattsc m2
w0+400/fs
frequency
Power Density
0-10
1.73
-325 304Wavenumber, mm-1
x 1017 wattsc m2
Power Density
viewer
Viewer
Transformation to Frequency Domain
Propagationto arbitrary
z
tit Ni ..1
R, mm
R. M. Bionta
FEL spatial FWHM downstream FEL spatial FWHM downstream of undulator exit, of undulator exit, l l = 0.15 nm= 0.15 nm
Transverse beam profile atundulator exit
Transverse beam profile15 m downstream of
undulator exit
FWHM vs. z at l = 0.15 nm
0
100
200
300
400
500
0 100 200 300
distance from undulator exit, meters
FW
HM
, mic
ron
s
Ginger(points)
Gaussian Beam(line)
R. M. Bionta
Total power at undulator exitTotal power at undulator exit
Total FEL Power
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
0.00 0.50 1.00 1.50 2.00
wavelength, nm
Gig
a-W
atts
Ginger simulations
Theoretical FEL saturation level
•10 Ginger simulations were run at different electron energies but with fixed electron emittance through 100 meter LCLS undulator.
•The Ginger runs at the longer wavelengths were not optimized, resulting in significant post-saturation effects. Results at longer wavelengths carry greater uncertanty.
R. M. Bionta
RMS BandwidthRMS Bandwidth
0
w0 = 12558 /fsw0 - 50 / fs
3
x 1
017
w
att
sc
m2
w0 + 50 /fs
frequency
Po
we
r D
en
sit
y
l= 0.15 nmTime Domain
l= 0.15 nmFrequency Domain
rms BW (%) vs wavelength (nm)
0.00
0.10
0.20
0.30
0.40
0.0 1.0 2.0
wavelength (nm)rm
s B
W (
%)
R. M. Bionta
FWHM vs wavelength at selected distances from undulator exit
0
250
500
750
1000
0.0 0.5 1.0 1.5
wavelength, nm
FW
HM
, mic
ron
s Ginger, 0 mGauss, 0 mGinger, 75 mGauss, 75 mGinger, 300 mGauss, 300 m
300 meters
75 meters
0 meters
FWHM vs. wavelength at 0, 75 FWHM vs. wavelength at 0, 75 and 300 metersand 300 meters
R. M. Bionta
We can confidently calculate the dose to transmissive We can confidently calculate the dose to transmissive optics.optics.
Low Z materials for transmissive optics can be chosen to survive in the LCLS experimental halls in the simple dose model on the left. The survivability of common high Z reflectors depends on additional assumptions.
Transmissive Dose Model
X-ray Photon
electron
atoms
Reflective Dose Model
R. M. Bionta
Dose / Power ConsiderationsDose / Power Considerations
0.01
0.1
1
10
100
100 1000 10000
Photon energy (eV)
Flu
en
ce (
J/cm
^2
)
undulatorexitexperimentalhall A
experimentalhall B
C
Si
W
Au
Be
0.01
0.1
1
10
0.1 1 10 100
grazing angle (degrees)
energ
y d
ensit
y c
orr
ect
ion
0.8 keV critical angle
0.8 keV
8 keV critical angle
8 keV
with electroncorrection
no electroncorrection
Fluence to Melt
Energy Density Reduction of a
Reflector
Be will melt at normal incidence at E < 3 KeV near undulator exit.
Using Be as a grazing incidence reflector may gain x 10 in tolerance.
R. M. Bionta
Front End Enclosure LayoutFront End Enclosure Layout
ValvePump
Pump
Slow valveFast valveFixed Mask
Slits
Diagnostics
WindowlessIon Chamber
Gas Attenuator
Solid Attenuator
Slits
Diagnostics
PPS
40mWestFace Near Hall
33mWestFace Dump
16.226 mEastface Last Dump MagWestface front End Enclosure
10.5 m
0 mEnd of Undulator
R. M. Bionta
Adjustable High-Power SlitsAdjustable High-Power SlitsAdjustable High-Power SlitsAdjustable High-Power SlitsIntended to intercept Intended to intercept
spontaneous beam, not FEL spontaneous beam, not FEL beam -- but will come very beam -- but will come very close, so peak power is an issueclose, so peak power is an issue
Two concepts being pursued Two concepts being pursued for slit jaws for slit jaws
Treat jaw as mirror (high-Z Treat jaw as mirror (high-Z material)material)
Treat jaw as absorber (low-Treat jaw as absorber (low-Z materialZ material
Either concept requires long Either concept requires long jaws with precision motionjaws with precision motion
Mechanical design based on Mechanical design based on SLAC collimator for high-energy SLAC collimator for high-energy electron beamelectron beam
R. M. Bionta
Front End Diagnostic TankFront End Diagnostic Tank
Direct Imager
Indirect Imager
ION Chamber
Turbo pump
Space for
calorimeter
BeIsolation
valve
Solid Filter Wheel Assembly
R. M. Bionta
Prototype LCLS X-Ray imaging cameraPrototype LCLS X-Ray imaging camera
CCDCamera
MicroscopeObjective
LSO or YAG:Ce crystal prism assembly
X-ray beam
X-ray beam
R. M. Bionta
Be Mirror Reflectivity
1.E-08
1.E-07
1.E-06
1.E-05
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Angle (degrees)
R
Indirect ImagerIndirect Imager
Be Mirror Reflectivity at 8 KeVBe Mirror Reflectivity at 8 KeV
1
0.1
0.01
0.001
0.0001
Be MirrorBe Mirror
Be Mirror angle provides "gain" adjustment Be Mirror angle provides "gain" adjustment over several orders of magnitudeover several orders of magnitude
R. M. Bionta
Multilayer allows higher angle and higher Multilayer allows higher angle and higher transmision but high z layer gets high dosetransmision but high z layer gets high dose
Be Mirror needs grazing incidence, camera close to beamBe Mirror needs grazing incidence, camera close to beam
Single high Z layer tamped by Be may hold togetherSingle high Z layer tamped by Be may hold together
R. M. Bionta
First check CCD by measuring First check CCD by measuring Response Equation CoefficientsResponse Equation Coefficients
crcrcrcrcr PtDCLQGd ,,,,, )(
crd ,
G
dQEL crcr )()( ,,
crDC ,
crQ ,
crP ,
t
Digitized gray level of pixel in row r, column c.
Electronic gain in units grays/photo electron.
Signal in units photo electrons.
Pixel Sensitivity non-uniformity correction.
Pixel Dark Current in units photo electrons/msec.
Pixel fixed-pattern in units grays.
Integration time in units msec.
R. M. Bionta
Photon Transfer CurvePhoton Transfer Curve
crcrcr PGtdGt ,Readout2
,,2 )()(
cr
crpixels
cr tdN
td,
,, )(1
)( Temporal mean gray level of pixel r,c.
cr
crcrpixels
cr tdtdN
t,
2,,,
2 )()(1
1)(
Temporal gray level fluctuations of pixel r,c.
R. M. Bionta
Calibration Data for one pixelCalibration Data for one pixel
Sigma Squared Vs. Mean
0
2000
4000
6000
8000
10000
12000
0 10000 20000 30000 40000 50000 60000 70000
Mean gray
Sigm
a Sq
uare
d
Mean gray vs. time
0
10000
20000
30000
40000
50000
60000
70000
0 1000 2000 3000 4000 5000 6000 7000
time, milliseconds
Me
an
Gra
y
crcrcr PGtdGt ,Readout2
,,2 )()(
crcrcrcrcr PtDCLQGd ,,,,, )(
R. M. Bionta
Photon Monte Carlo Simulations for predicting lens and Photon Monte Carlo Simulations for predicting lens and camera performancecamera performance
4,0002,0000-2,000-4,000
4,000
3,000
2,000
1,000
0
-1,000
-2,000
-3,000
-4,000
-5,000
SPEAR source simulation
Visible photons
X, microns
Y, m
icro
ns
LSO25 Exit Z
403020100
450
400
350
300
250
200
150
100
50
0
MonteCarlo
Bend
LSO
5,0000-5,000-10,000
8,000
6,000
4,000
2,000
0
-2,000
-4,000
-6,000
-8,000
-10,000
5,0000-5,000-10,000
8,000
6,000
4,000
2,000
0
-2,000
-4,000
-6,000
-8,000
-10,000
X Ray Photons
R. M. Bionta
Direct Imager Version 1 efficiencyDirect Imager Version 1 efficiencyCCD pixel size, microns 24 24 24 24 24 24 24 24Objective power 2.5 2.5 2.5 2.5 20 20 20 20Object Pixel Size 9.6 9.6 9.6 9.6 1.2 1.2 1.2 1.2Object FOV, mm 10 10 10 10 1 1 1 1Scintillator material LSO LSO LSO YAG LSO LSO LSO YAGCentral Wavelength (nm) 415 415 415 526 415 415 415 526Scintillator Thickness, microns 100 50 25 100 100 50 25 100Visible Photons/8 KeV interaction 248 248 248 66 248 248 248 66Solid angle efficiency % 0.05 0.05 0.05 0.05 0.7 0.7 0.7 0.7glue scintillator interface efficiency % 99.8 99.8 99.8 99.8 100 100 100 100prism glue interface efficiency % 98.5 98.5 98.5 98.5 98.5 98.5 98.5 98.5prism transmission efficiency % 100 100 100 100 100 100 100 100mirror reflection efficiency % 94 94 94 97.8 94 94 94 97.8Objective transmission efficiency % 99.7 99.7 99.7 99.9 99.7 99.7 99.7 99.9CCD Quantum Deficiency % 62.4 62.4 62.4 71.3 62.4 62.4 62.4 71.3Photo electrons/interacting x-ray 0.068 0.068 0.068 0.021 0.955 0.955 0.955 0.304Photosn/Gray 74 74 74 238 5 5 5 16Scintillator efficiency % 100 98.4 87.2 94.6 100 98.4 87.2 94.6Time to fill well at SSRL bend, minutes 3.1 3.2 3.6 10 14 14 16 47Attenuation needed at LCLS to fill well 2.E-04 2.E-04 2.E-04 6.E-04 7.E-04 8.E-04 9.E-04 2.E-03
R. M. Bionta
Camera Sensitivity Measurements at Camera Sensitivity Measurements at SPEAR 10-2SPEAR 10-2
Horizontal Vertical
<----10 mm----->
Photon Rate at Camera
Sum-of-Greys/Second3.000E+102.000E+101.000E+100.000E+00
#P
hoto
ns/S
ec
1.40E+12
1.30E+12
1.20E+12
1.10E+12
1.00E+12
9.00E+11
8.00E+11
7.00E+11
6.00E+11
5.00E+11
4.00E+11
3.00E+11
2.00E+11
1.00E+11
0.00E+00
F i t t o crgGbn ,
I n f r o n t o f c a m e r a w i n d o w A t s c i n t i l l a t o r
I t e m F i t E r r o r U n i t s I t e m F i t E r r o r U n i t s
G 3 9 . 4 0 . 1 / g G 3 1 . 1 0 . 1 / g
b - 1 . 1 x 1 0 1 0 0 . 3 x 1 0 1 0 b - 0 . 9 x 1 0 1 0 0 . 3 x 1 0 1 0
Sum of gray levels
Ion Chamber Photon rate
attenuator
Imaging camera
Ion chamber
R. M. Bionta
Measured and predicted Measured and predicted sensitivities in fair agreementsensitivities in fair agreement
Measured and Predicted Sensitivity
020406080
100120140160180
0 10000 20000 30000
Photon Energy, eV
Ph
oto
ns/g
ray
Pred Ver 1
Meas Ver 1
Meas Ver 2
Pred Ver 2
R. M. Bionta
Camera Resolution ModelCamera Resolution ModelSource Dobj Dimg Objective Crystal Rdiffract Rdepth RSourceX RSourceY TotalX TotalY
SPEARBend 18.670 0.050 20x YAG100 3.1 8.4 2.1 0.5 9.2 8.9SPEARBend 18.670 0.050 20x LSO100 2.5 8.4 2.1 0.5 9.0 8.7SPEARBend 18.670 0.050 20x LSO50 2.5 4.2 2.1 0.5 5.3 4.9SPEARBend 18.670 0.050 20x LSO25 2.5 2.1 2.1 0.5 3.9 3.3SPEARBend 18.670 0.050 20x YAG20 3.1 1.7 2.1 0.5 4.1 3.6SPEARBend 18.670 0.050 20x YAG5 3.1 0.4 2.1 0.5 3.8 3.2
SPEARBend 18.670 0.050 2.5x Zeiss YAG100 9.6 2.8 2.1 0.5 10.2 10.0SPEARBend 18.670 0.050 2.5x Zeiss LSO100 7.5 2.8 2.1 0.5 8.3 8.0SPEARBend 18.670 0.050 2.5x Zeiss LSO50 7.5 1.4 2.1 0.5 8.0 7.7SPEARBend 18.670 0.050 2.5x Zeiss LSO25 7.5 0.7 2.1 0.5 7.9 7.6SPEARBend 18.670 0.050 2.5x Zeiss YAG20 9.6 0.6 2.1 0.5 9.8 9.6SPEARBend 18.670 0.050 2.5x Zeiss YAG5 9.6 0.1 2.1 0.5 9.8 9.6
SPEARBend 18.670 0.050 5x Zeiss YAG100 3.8 6.9 2.1 0.5 8.2 7.9SPEARBend 18.670 0.050 5x Zeiss LSO100 3.0 6.9 2.1 0.5 7.8 7.6SPEARBend 18.670 0.050 5x Zeiss LSO50 3.0 3.5 2.1 0.5 5.0 4.6SPEARBend 18.670 0.050 5x Zeiss LSO25 3.0 1.7 2.1 0.5 4.1 3.5SPEARBend 18.670 0.050 5x Zeiss YAG20 3.8 1.4 2.1 0.5 4.6 4.1SPEARBend 18.670 0.050 5x Zeiss YAG5 3.8 0.3 2.1 0.5 4.4 3.8
R. M. Bionta
Camera Resolution in qualitative Camera Resolution in qualitative agreement with modelsagreement with models
1.5 mm
1.1 mm
1.5 mm
R. M. Bionta
Camera Resolution Quantitative Data Camera Resolution Quantitative Data Analysis in progressAnalysis in progress
R. M. Bionta
Micro Strip Ion ChamberMicro Strip Ion Chamber
Differentialpump
Differentialpump
Cathodes
Segmented horizontal
and vertical anodes
Isolation valve with
Be windowWindowless
FEL entry
R. M. Bionta
Gas AttenuatorGas AttenuatorGas AttenuatorGas Attenuator
For use when solid absorber risks damage (low-E FEL, front end)For use when solid absorber risks damage (low-E FEL, front end)Windowless, adjustable attenuationWindowless, adjustable attenuationCan provide up to 4 orders of magnitude attenuationCan provide up to 4 orders of magnitude attenuation
R. M. Bionta
Solid AttenuatorSolid AttenuatorSolid AttenuatorSolid Attenuator
BB44C attenuators can tolerate C attenuators can tolerate FEL beam at E > 4 keV in FEL beam at E > 4 keV in FEE, and at all energies in FEE, and at all energies in experimental hutchesexperimental hutches
Linear/log configurationsLinear/log configurations
Can be wedged in 2 Can be wedged in 2 dimensions for continuously dimensions for continuously variable attenuationvariable attenuation
Translation stages provide Translation stages provide precision X and Y motionprecision X and Y motion
R. M. Bionta
MissingMissing
• Predicted performance of direct and indirect imager for Spontanous vs. I, and FEL vs. Power
• Calculations of linearity and signal levels in Ion chamber
• Integration with FEE + Beam Dump floor plan
R. M. Bionta
Commissioning DiagnosticsCommissioning Diagnostics
Measurements– Total energy– Pulse length– Photon energy spectra– Spatial coherence– Spatial shape and centroid– Divergence
R. M. Bionta
Commissioning diagnostic tankCommissioning diagnostic tank
ApertureStage
“Optic”Stage
Detector and attenuatorStage
Rail alignment StagesRail
R. M. Bionta
Total EnergyTotal Energy
Crossed aperturesOn positioning stages
absorber
Temperaturesensor
AttenuatorScintillator
Absorber Dose 2 x FWHM 4 x attn lngtheV/atom microns microns
0.8 KeV Be 0.02 1918 208 KeV Si 0.12 338 310
Poor ThermalConductor
HeatSink
R. M. Bionta
Photon Spectra MeasurementPhoton Spectra Measurement
ApertureStage
Crystal (8KeV)Grating (0.8 KeV)
Stage
Detector and attenuatorStage
X ray enhanced linear array and stage
R. M. Bionta
Spatial Coherence MeasurementSpatial Coherence Measurement
SlitsStage
Detector and attenuatorStage
Array of double slits
R. M. Bionta
Spatial shape, centroid , and Spatial shape, centroid , and divergencedivergence
•FEE:•A1 •A2 •A4
FFTBHALL A
DiagnosticTanksFEE 1 & 3:
DiagnosticTankA1-1
CommissioningDiagnosticTankA4-1
Spatial shape, centroid , and divergence measured by combining data from the imagers in these tanks.
R. M. Bionta
Rad Sensor - a candidate technology for LCLS pulse Rad Sensor - a candidate technology for LCLS pulse length measurement and pump probe synchronizationlength measurement and pump probe synchronization
Rad sensor is an InGaAs optical wave guide with a band gap near the 1550
nm.
1550 nm optical carrier
Reference leg
Detectorbeam splitter
1550 nm optical carrier
Fiber Optic Interferometer
Rad sensor is inserted into one leg of a fiber-optic
interferometer.
X-Rays strike the rad sensor disturbing the waveguide’s electronic structure.
This causes a phase change in the interferometer. The process is believed
to occur with timescales < 100 fs.
X-Ray Photons
Point of interference X-Ray induced phase change observed as
an intensity modulation at point of interference
X-Ray measurements of the time structure of the SPEAR beam in January and March 2003 confirmed the devices x-ray sensitivity for LCLS applications.
time
phas
e
SPEARSingle electron
bunch mode
Mark Lowry,
R. M. Bionta
NIF Rad-Sensor Experimental Layout at SLACNIF Rad-Sensor Experimental Layout at SLAC
Ion chamber
attenuatorImaging cameraDiamond
PCDRadSensor
slit
R. M. Bionta
RadSensor Response to single-bucket fill pattern
•Fast rise•Long fall-time will be improved•Complementary outputs =>
•index modulation
Xray pulse history (conventional)
781 ns
Mark Lowry
R. M. Bionta
Significant Improvements in sensitivity are realized near the band edgeSignificant Improvements in sensitivity are realized near the band edge
Systematic spectral measurements of both index and absorption under xray illumination must be made to get a clear understanding of the sensitivity available
Absorption width = 0.01 nm
Absorption width = 1 nm
•Adding in x4 for QC enhancement we should detect a single xray photon at least 8x10-4 fringe fractions.
•If we allow for a cavity with finesse 10-100, this allow the development of a useful instrument
Data to date
= exciton abs peak widthFrom Gibbs, pg 137
Absorption edge at 1214 nm
Mark Lowry
R. M. Bionta
XRTOD Diagnostics TimelineXRTOD Diagnostics Timeline• FY04 – PED year 4
– PCMS certification - Jan 2004– Baseline Review - Aug 2003– Complete simulations of camera response to FEL and Spontanous– Prototype Windowless Ion Chamber / gas attenuator
• FY05 – PED year 3– FEE Detailed design
• FY06 - Start of Construction– FEE Build and test– NEH Design
• FY07– FEE Install– NEH Build and Test– FEH Design
• FY08– NEH Install– FEH Build and Test
• FY09 - Start of Operation
R. M. Bionta
FEE Diagnostics ComissioningFEE Diagnostics Comissioning
• Start with Low Power Spontaneous– Saturate DI, measure linearity with solid
attenuators– Test Gas Attenuator
• Raise Power, Look for FEL– in DI, switch to Indirect Imager when attenuator
burns– Move behind Gas Attenuator– Move to Comissioning Diagnostic Tank
Attenuator
DirectImager Indirect
Imager
IonChamber Attenuator
DirectImager Indirect
Imager
IonChamber
Gas Attenuator
Recommended