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BROOKHAVEN SCIENCE ASSOCIATESU.S. Department of Energy
Office of Basic Energy Sciences
Funded under contract: DE-AC02-98CH10886
How Will NSLS-II Serve Infrared Science?
Larry Carr, Lisa Miller, Randy SmithNSLS Infrared
and the NSLS-II design team
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Synchrotron Infrared Source Qualities
• High brightness– ~ 3 orders of magnitude higher than conventional “white” IR
spectroscopy sources.– Needed for throughput limited spectroscopy (microspectroscopy)
• Broad spectral coverage– everything from visible down to microwaves, though weaker at
long wavelengths.– Compatible with high-performance FTIR spectrometry.
• Pulsed output– 10s of picoseconds out to nanoseconds– Time-resolved spectroscopy / dynamics
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
High Brightness Enables Throughput Limited Techniques
Microscopy atdiffraction-limit
Spectroscopy of materialsunder extreme conditions:
• diamond anvil cells• complex cryostats & magnets
Very high (spectral) resolution(requires small collimating aperture)
r = f (2δν/ν)1/2 = 2 mmfor f = 20 cm, δν = 0.001 and ν = 20 cm-1
Restrictive angle of incidence• Grazing incidence• Attenuated total refl. (ATR)• Ellipsometry
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Worldwide Synchrotron Radiation Facilities for Infrared
NSLSBNL
ALSLBL
CAMDLSU
SRCUW
SRSDaresbury
CLSUSask
UVSORIMS
SPring-8
MAXLund
SoleilLURE
ESRF
SRRC
SSLS
(Australian)Monash
SLSPSI
BESSY II
ANKAFZK
DAΦNE
Elettra
HSLS
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Synchrotron Infrared Brightness
If electron energy issufficiently high (> 100 MeV)then IR brightness dependsonly on:
- beam current
- source size/emittance
- extraction aperture
10-4 10-3 10-2 10-1 100 101 102 103 104
0.1
1
10
Spe
ctra
l dis
tribu
tion
(dP
/dω)
Photon Energy [eV]
10-1 100 101 102 103 104 105 106
THz
( ) 31
~ ωρ
2 GeV
25 MeV
0.2 GeV
~ 2 meter bend
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
TSGM: 180-1200eV (1995)
TSGM: 7-288eV (1999)
SGM: 15-1200eV (1996)
TSGM: 100-900eV (1999)
NIM: 3-30eV (1998)
White
White
125µeV-600meV (1997)
A: 2.5meV-3.1eV (1999)B: 48-840meV (1998)
1.2-480meV (1987)
A: 2.5meV-2eV (1999)B: 2.5meV-2eV (1998)
NSLS VUV800 MeV
1000 mA at injection
SGM: 8-250eV (1996)
Recently Upgraded VUV/IR Beamlines
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
IR Performance of VUV Ring: 90x90mr Extraction
1 10 100 100010-9
10-6
10-3
100
B
right
ness
[W/c
m-1/(c
m2 -r
ad2 )]
Frequency [cm-1]
Ideal 700mA VUV-IR 700mA
10000 1000 100 10
Wavelength [µm]
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Infrared Performance: NSLS VUV Ring
2 4 6 8 100.1
1
10
100
NSLS U12IR"single beam"
intensity
synchrotron HiP Hg Arc
Sig
nal I
nten
sity
Frequency [cm-1]
0 5 10 15 20 25 30 350.994
0.996
0.998
1.000
1.002
1.004
1.006
Rat
io (1
00%
line
)
Frequency [cm-1]
100 1000
1
10
100
Relative SignalU10A Synch/Globar1 mm diam. aperture, f/4
Rat
io
Frequency [cm-1]
0 100 200 300 400 5000.95
1.00
1.05
BB (1200K globar) Synchrotron U10A
100% line comparison1 mm specimen aperture
Rat
io
Frequency [cm-1]
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Pulses for Time-Resolved Spectroscopy
• Synchronized M-L laser(<10 ps pulses)& VUV ring pulses(down to 300 ps).
• Need shortersynchrotron pulses(down to 100 fs, butany gain is useful)
140 160 180 200 220-2
0
2
4
6
8
10
Det
ecto
r si
gnal
Time [ns]
laser synchrotron
4 ns
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Existing IR Programs/Activities• Biological and Life Sciences
– vibrational microscopy/imaging of proteins and cell structures– bone mineralization osteoporosis/osteoarthritis– chemistry of diseased tissues at the cellular level
• Environmental and Space Sciences– vibrational microspectroscopy of soils and interplanetary particles
• Corrosion and Catalysis– grazing incidence spectroscopy of molecular layers on metal surfaces
• Geosciences– spectroscopy and microscopy of molecular solids and minerals at extreme
pressures and temperatures.• Materials
– infrared conductivity of complex metal oxides.– dynamics (time-resolved) in superconductors and nanomaterials.– spectroscopy of spins and magnetic resonances in ordered solids.
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Infrared Considerations for NSLS-II
• Existing NSLS & VUV/IR Ring– high current (high brightness), ~ 1 ns duration pulses– ~ 25 years old (increasing maintenance for linac, booster, RF systems)– ring chamber and magnets remain reliable
• NSLS-II: New Ultra-Bright Storage Ring for X-rays– 500 ma (top-off)– new injector– 500 MHz
• at least 10X shorter bunches– but large aperture ports could be problematic
• estimate 20 mrad from geometric considerations.
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
1 10 100 1000
10-9
10-6
10-3
100
Brig
htne
ss [W
/cm
-1/(c
m2 -r
ad2 )]
Frequency [cm-1]
Ideal 700mA VUV-IR 700mA NSLS-II 500mA
Infrared on the NSLS-II Main Ring?
10 100 10000.0
0.5
1.0NSLS-II / VUV-IR
Rel
ativ
e B
right
ness
Frequency [cm-1]
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Plan: Relocate VUV/IR to NSLS-II: Infrared Ring
• Maintain investment in ring chamber, magnets andbeamline front-ends
• NSLS-II -> new injector (Linac)– Top-off injection for IR too
• can tolerate modes with shorter lifetimes– brighter mid-IR beam– higher average current (1 A)– short bunch lattice
• New RF– 500 MHz to match NSLS-II systems
• intrinsically shorter bunches (10s of picoseconds)• possible coherent mode?
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
The NSLS-II Project
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
NSLS-II Infrared Ring
Option 1:200 MeV linac + BoosterInject IR ring at 200 MeV
Option 2:3 GeV linacInject IR Ring at up to 800 MeV
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Infrared Brightness Comparison
1 10 100 100010-9
10-6
10-3
100
B
right
ness
[W/c
m-1/(c
m2 -r
ad2 )]
Frequency [cm-1]
VUV t/o 1000mA VUV-IR 700mA NSLS-II 500mA
10000 1000 100 10
Wavelength [µm]
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
SGM: 8-250eV (1996)
NIM: 3-30eV (1998)
White
White
1.2-480meV (1987)
A: 2.5meV-2eV (1999)B: 2.5meV-2eV (1998)
NSLS VUV800 MeV
1000 mA atinjection
A: 2.5meV-3.1eV (1999)B: 48-840meV (1998) 125µeV-600meV (1997)
Possible Infrared Beam Ports
Chamber modificationfor a U16IR Far-IR port(magnetospectroscopy)
Chamber modificationfor a U7/8 extendedsource (imaging arraymicroscopy)
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Two 25 mrad by 100 mrad ports
Extended Source for Small Array FTIR Microspectrometer
• Rapid scan FTIR with 16 element array detector
• Full spectral range MCT
25µm
25µm
Detector schematic
Perkin-Elmer “Spotlight”IR microscope with linear detector array
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Rough / Strawman Elevation Drawings
Linac below grade to use earth shielding
Main NSLS-II RingMain NSLS-II Ring(cross section)(cross section)
Infrared RingInfrared Ring
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Rough Infrared Ring and Beamline Strawman / Schematic
• Infrared beamlines extract light from ring (below grade)
• Endstations on upper level (stable concrete support)
• Most of ring covered (additional useful floor space, walkways)
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Other Possibilities: Coherent Emission
• Abo-Bakr et al demonstrate stable coherent emission from BESSY II (PRL March 2003)
• Berkeley Lab proposal for CIRCE (storage ring primarily for coherent far-IR)
Incoherent@ 1000 ma
BROOKHAVEN SCIENCE ASSOCIATES
National Synchrotron Light Source U.S. Department of EnergyOffice of Basic Energy Sciences
Summary & Questions
Current plans call for relocating NSLS VUV/IR Ring to NSLS-II• Space for additional ports and beamline endstations
– Let’s make sure it’s all stable!• beamline hutches for environment stability?
– extended source based on 200 mrad horizontal (two U10 or U2 ports)?New Imaging Capability
• Top-off mode for higher current and higher brightness– how often?, how stable?
• 500 MHz RF– shorter bunches … modes for very short?– coherent emission?
• At least 200 MeV– adequate for IR and Visible, but may need more to avoid excessive topping-off– higher energy -> undulators could serve as tunable pump for time-resolved
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