Low Energy Neutron Source Center for the Exploration of Energy and Matter The Low Energy Neutron Source – C S dF Pl Current Status and Future Plans Paul Sokol Paul Sokol Indiana University Thomas Rinckel , Roger Pynn, Helmut Kaiser , Warren Garfield, Helmut Kaiser , Warren Garfield, Dobrin Bossev, David V. Baxter UCANS-II 2011 6 July 2011
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Low Energy Neutron SourceCenter for the Exploration of Energy and Matter
The Low Energy Neutron Source –C S d F PlCurrent Status and Future Plans
Paul SokolPaul SokolIndiana University
Thomas Rinckel , Roger Pynn, Helmut Kaiser, Warren Garfield,Helmut Kaiser, Warren Garfield, Dobrin Bossev, David V. Baxter
UCANS-II 2011 6 July 2011
Outline• Current Status
– Facility Operations• Accelerator• Target and Moderator• Instruments and Endstations
– Scientific and User Programs• SANS
• Future ProspectsFacility OperationsSANS
– Micelles– Viruses– Rocks
• Moderator DevelopmentR di ti Eff t
– Facility Operations• Accelerator
– Improved reliability– Full Power Operation– Performance upgrade
18 /100 A i• Radiation Effects• Radiography
– 18 MeV/100 mA operation
• Target and Moderator• Higher performance
moderators• Alternative target cooling• Alternative target cooling
• Instrumentation and Endstations• SESAME• Powder Diffractometer
i
UCANS-II 2011 6 July 2011
• Test Beam Line• Radiation Effects• Radiography
The Low Energy Neutron Sourcelow-energy (p,nx) reactions (Ep<13MeV) in Be.
cold moderator (e g solid CH atcold moderator (e.g. solid CH4 at 1K<T<40K).
variable pulse width (from ~10 s to more than 1 0 ms)to more than 1.0 ms).
Accelerator•13 MeV Linac•~25 mA Peak Current•~2 mS pulse width
Instruments•SANS
•13 kW Average PowerTarget
•10x10 cm2
4 2 1013 /
UCANS-II 2011 6 July 2011
SANS•SESAME
•4.2 x 1013 n/s
LENS AcceleratorAccelerator•13 MeV Linac•25 mA Peak Current•25 mA Peak Current•~2 mS pulse width•13 kW Average Power
4 MeV DTL6 MeV DTL
Operating at full peak power•Routine operation at 4 kW
•400 S pulse width•Short term operation at 6kW
25 KV Pulsed Ion Source3 MeV RFQ
4 MeV DTL •Short term operation at 6kW
RF System•3 ‐ 1.25 MWatt Klystrons•11 uF Cap (50 kJoules)
Switch tubes are biggest problem•Rated at 100 kV, operated at 85 kV•Break down ~every 6hrs
UCANS-II 2011 6 July 2011
11 uF Cap (50 kJoules)•92 kV 5 amp Power Supply
y•New tubes (150 kV) ready to test
•Rinckel – Poster 21
Target, Moderator and Reflector
Nonlinear beam optics to provide even power distribution
Moderator•6 K Operation•Solid MethaneSolid Methane
Be Target•Design
•Original ‐ 4 mm thick Be •Current – 1.1 mm thick Be•Stopping distance 1.28 mm
•Water Cooling – 6 GPM•Peak Heat flux – 3 MW/m2
UCANS-II 2011 6 July 2011
Peak Heat flux 3 MW/m•Target Power 12 kWFast Valve for Accelerator Protection
Rinckel Thursday 11:45
SANSRunning for Science Program
• PFP = 8.0 m
• SFP 1 0 m to 4 5 m• SFP 1.0 m to 4.5 m– Qmin = 0.06 nm‐1
– =2 0 nm 20 Hz– max=2.0 nm, 20 Hz• SCIENCE:
– Structure of surface‐functionalized nanoparticlesnanoparticles
– Complex fluids (surfactants, clay slurries, …)
Polymer networks
UCANS-II 2011 6 July 2011
– Polymer networks
– Glasses/crystalization
LENS SESAME(Spin Echo Scattering Angle Measurement)p g g
Wollaston PrismFirst beam in April 2009Currently in commissioning phase
2/ 2/
Z
Currently in commissioning phase
sample
2
PolarizedGuide Sections
3 4
BENDER
mptor
AnalyzerSupermirror/ 3He
Tri. coils
SAMPLESTAGE Mode of operation
Shutter
1 2
Wall
3 4
Beam
dum
Detect •Transmission (SANS)
•Reflectometry(solids & liquids)
UCANS-II 2011 6 July 2011
WallTMR PFP SFP
Low Energy Neutron SourceCenter for the Exploration of Energy and Matter
Micelles - aggregates of surfactant molecules self-assembled in aqueous solutions
Size of head group; length and number of tails; charge on surfactant; temperature; concentration; flow conditions
Fully liquidation of CO2 occurs around 700psi in porous coal (830psi in bulk CO2); Porosity decreases as pressure up; Dm increases in large pores, Ds decreases in small pores as pressure up;
l di i i di b l i di i h i f b
UCANS-II 2011 6 July 2011
Fractal dimension intending to be close 3, indicating a very rough interface between pore-matrix
Imaging
UCANS-II 2011 6 July 2011
UCANS-II 2011 6 July 2011
Moderator Research
10
100
400 K40 K10 K4 K
Significant interest in cold and very cold neutrons
0.01
0.1
1•Large scale structures•Fundamental Physics
S i i f i
• Validation/development of scattering kernels:0.0001
0.001
0.01 0.1 1 10 100 1000
LENS is ideal for exploring new materials and concepts
Validation/development of scattering kernels:– Methane phase II– VCN/UCN candidate material investigations– Total cross-section measurementsTotal cross section measurements
• Bench tests of new ideas/geometries– SNS poison burn-up issues
Be filter/reflector
UCANS-II 2011 6 July 2011
– Be filter/reflector – Spin equilibration
Moderator Research at Moderator Research at LENS
UCANS-II 2011 6 July 2011
Radiation Effects StudiesSecond target station optimized for radiation damage studies Electronics irradiationLow energy testing
1-10 MeV
Silicon
Base-Emitter saturation voltage (VBESAT)
UCANS-II 2011 6 July 2011
Damage
Future PlansFuture Plans• Accelerator
– Improve reliability• Klystron Switch tubes
– Full Power Operation• Reduce losses
I d• Increase stored energy– More capacitors
– Long Term •Target– Long Term• Increase Energy (18
MeV)
•Target•Alternative Cooling•Gallium Loop
UCANS-II 2011 6 July 2011
• Increase Power (100 mA)
Moderator Development•Higher performance moderators
•LENS, …•SNS, Lujan, ISIS, …
New Moderator Concepts
UCANS-II 2011 6 July 2011
InstrumentationBring existing instrumentation
on line (SESAME)( )
Develop new capabilities
Multiplexed TOFDiffractometer
Test Beam Linecross sectionsemission time
L12 L2S
Diffractometeroptics studies
N I t t tiNew InstrumentationLong pulsed sources
UCANS-II 2011 6 July 2011
Optimize FacilitiespCurrent TMR1
R di i EffRadiation Effects
UCANS-II 2011 6 July 2011
10cm x 10cm Sample access
Develop ApplicationsDevelop user communities
Traditional UsesPhysicsChemistryBiology
New CommunitiesAnthropologyPaleontologyPaleontologyArt Conservation
UCANS-II 2011 6 July 2011
Conclusions•• LENS is operationalLENS is operational