UK R&D Infrastructures and Accelerator Programmes

Jim ClarkeSTFC Daresbury Laboratory

TIARA-PP Final MeetingDaresbury Laboratory

25th November 2013

Outline• National Accelerator Facilities

– Diamond Light Source– ISIS Neutron Source

• Test Accelerators– FETS– MICE– ALICE– EMMA– VELA– CLARA– ALPHA-X

• Summary2

3 GeV electron storage ring generating bright, stable, light enabling high quality research across a broad research base:

– Chemistry– Cultural Heritage– Earth Science– Engineering– Environmental Science– Life Sciences– Physics and Material

Science

Diamond Light Source

Diamond Light Source at Rutherford Appleton Laboratory

3http://www.diamond.ac.uk/

Richard P. Walker

Normal beam mode Low-emittance beam mode

Compound Refractive Lenses CRLS – 18 lenses Photon Energy ~15 keVSource demagnification: 3.7m / 44m (~1/12)Knife edge scans using 200 µm Au wire

10 15 20 25 30

0.0

0.5

1.0

De

riva

tive

Y1

piezo1y [m]

Derivative Y1 Gauss of Derivative Y1

3.8 m

-19.830 -19.825 -19.820 -19.815 -19.810

0

5

10

15

20

De

riva

tive

Y1

tbdetY [mm]

Derivative Y1 Gauss of Derivative Y1

5.8 m

CRL

44m3.7m

DCM

B16-BM µ-focusE=15 keV

Low-coupling mode: Micro-focusing• Vertical coupling reduced from 1% to 0.3% during operations• Low coupling smaller source smaller focused beam

Þ Focused beam size at sample reduced by 35%

Richard P. Walker

Low-coupling mode: Nano-focusing

• Low coupling smaller source smaller focused beam

Þ Nano-focused beam (v) also reduced (from 144 nm to 124 nm)

Fresnel Zone Plate – Z150/75/1W5 (150 µm diameter, 75 nm outer zone width)Source demagnification: 73 mm / 47m (~1/644)Knife edge scans using 200 µm Au wire FZP

47m73mm

DCM

B16-BM n-focusE=8 keV

Normal beam mode Low-emittance beam mode

3.849 3.850 3.851

0

1000

2000

De

riva

tive

Y 2

micospiezo1 [mm]

Derivative Y 2 Lorentz of Derivative Y 2

144 nm

3.849 3.850 3.851

0

300

600

900

Der

ivat

ive

Y1

micospiezo1 [mm]

Derivative Y1 Lorentz of Derivative Y1

124 nm

Brilliance improvement for Diamond

reduced coupling 1% 0.3%300 mA 500 mA

reducing diamond emittance with present hardware2.7 nm 2.1 nm lattice test – ongoing: issues with SCWs

Initial studies for an ultra low emittance lattice for Diamond-II

5BA 7BA, and modified 4BA

Thanks to T. Pulampong, R. Walker, J. Kay and N. Hammond

Brilliance upgrade at Diamond

Riccardo Bartolini

upgrade with Diamond-II (200pm): 300mA and 1%K

Brilliance plot using U27 – 72 periods 2 m long with Kmax = 2.02 10 mm gap Tuning curves computed with Spectra 8.0

Assuming the operation with a 200pm lattice

Riccardo Bartolini

doubling the number of beamlineswhile still pushing the emittance down

Modified 4BA - 320 pm

4BA with an additional short straight section between the dipole pairs

emittance not pushed as for a pure 4BA but can double the number of straight sections

Length of additional straight sections forced to be at least 3 m while keeping the remaining 6.7 m and 9 m straight sections

Riccardo Bartolini

Modified 4BA cell

Broken the 4 BA cell to leave 3 m space

12 quads per cell10 Sextupoles per cell

Straight section lengthslightly reduced11 m 9.7 m 8.3 m 6.7 m

Riccardo Bartolini

Modfied 4BA – one superperiod

Ring circumference shrinks from 561.6 to 561.0 -> loss 1 harmonic of RF

Parameters

Total lengthNatural emittanceNatural chromaticity : hor./ver.Straight length : long/short/middle

561.0 m314.7pm-rad-146.7/-85.6

9.7/6.7/3

Gradient in bend < 15 T/mQuads gradient < 70 T/m

Riccardo Bartolini

ISISISIS at Rutherford Appleton Laboratory

11http://www.isis.stfc.ac.uk/

Spallation neutron source based upon an 800 MeV proton synchrotron, enabling high quality science:

– Physics– Chemistry– Materials Science– Earth Science– Engineering– Biology

John Thomason

ISIS Injection Upgrade

• A New 180 MeV Injector Update old linacIncrease beam power ~0.5 MW

• AdvantagesReduces Space Charge (factor 2.6)

Chopped, Optimised Injection & Trapping

• ChallengesInjection straightActivation (180 MeV)Space charge, beam stability, ....

New 180 MeV Linac

70 MeV Linac

800 MeV Synchrotron

TS1

TS2

MICE

2 3

1

2

pinc

r NQ

B

John Thomason

• Snapshots of the work: challenges of getting 0.5 MW in the ISIS Ring

Longitudinal Dynamics

Transverse & Full Cycle 3D Dynamics

Injection

Other Essentials: Activation, Diagnostics

Analytical Work Simulation Results

Test

Dis

trib

utio

n

RF Bucket Variation of key parameters

Evolution of bunch

Accelerated distributions in (x,x’),(y,y’),(,dE)

Predicted Space Charge Limit

Coherent Tune Shift and Resonance

Single particle tune shift distributions at 0.5 MW

Injected distributions in (x,x’),(y,y’),(,dE)Foil temperatures

Injection StraightInjection Straight Modelling

Activation vs Energy Activation Measurements

Electron Cloud Monitor Strip-line Monitor/Kicker

ISIS Injection Upgrade Ring Physics Study

John Thomason

Head-tail instability Key for high intensity proton rings

New simulation code: Set 3DiModel losses, benchmark on ISIS

Ring High Intensity Beam Studies on ISIS

Half-integer intensity limit in proton ringsUsing the ISIS ring to study halo formation

(Y,Y)

Higher order loss effects and imagesInvestigating complex loss mechanisms

Image driven resonanceLoss vs Q measurement Vertical dipole motion along bunch on successive turns

Simulation Simulation Measurement

Y profile

• Some of our R&D Studies

Y profile

Turn

Sam

ples

alo

ng b

unch

Vertical difference signal(along bunch, many turns)

John Thomason

Front End Test Stand (FETS)

• FETS at Rutherford Appleton Laboratory aims to demonstrate key technologies for the front end of the next generation of high power pulsed proton accelerators.

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http://fets.isis.rl.ac.uk/

John Thomason

High brightness H– ion source• 4 kW peak-power arc

discharge• 60 mA, 0.25 π mm mrad beam• 2 ms, 50 Hz pulsed operation

Low Energy Beam Transport• Three-solenoid configuration• Space-charge neutralisation• 5600 litre/s total pumping

speed

Radio Frequency Quadrupole• Four-vane, 324 MHz, 3 MeV• 4 metre bolted construction• High power efficiency

Medium Energy Beam Transport• Re-buncher cavities and EM quads• Novel ‘fast-slow’ perfect chopping• Low emittance growth

Diagnostics• Non-interceptive• Well distributed• Laser-based

Front End Test Stand (FETS) John Thomason

FETS Ion Source R&D• FETS applications include:

• ISIS upgrades• Future Spallation Neutron Sources• Neutrino Factory• Waste Transmutation• ADSR

• FETS uses the ISIS Penning type ion source and is already delivering world class performance.

• The FETS specification is for a 60 mA beam in 2 ms pulses at 50 Hz.

εH = 0.38 πmm.mrad (norm rms)

εV = 0.37 πmm.mrad (norm rms)

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John Thomason

FETS Low Energy Beam Transport

• FETS uses a 3 solenoid magnetic LEBT to match the beam from the ion source into the RFQ.

Vertical emittance0.3 πmm.mRad rms norm

Horizontal emittance0.4 πmm.mRad rms norm

18John Thomason

Ion Source, LEBT and RFQ

• New high power, high duty factor ion source extraction power supply

• Low energy beam transport section alignment improved• Beam centred, symmetric in phase space and matched into RFQ• First metre section of Radio Frequency Quadrupole is at RAL• Remaining three metres in final machining stage• Cavity, vacuum and RF testing from Winter 2013 to Summer 2014• First RFQ beam anticipated late 2014

John Thomason

• Slow down muons in a light absorber, then re-accelerate in beam direction using RF cavities.

• All of which are immersed in a magnetic channel to confine the muon beam.

• MICE on ISIS will commission and operate a realistic section of cooling channel.

• Measure its performance in a variety of modes of operation and beam conditions.

• Results will allow future Neutrino Factory complex to be optimised.

Muon Ionisation Cooling Experiment (MICE)

20 http://mice.iit.edu/John Thomason

MICE Hardware DevelopmentTracker Focus Coil Absorber Cavity Module

200 MHz Cavity

RF Be Window Coupling Coil

21John Thomason

RF power specification achieved at Daresbury

Andrew Moss

Forward power into loadAmplifier system has been dismantled from Daresbury and is currently being installed in the MICE hall

Andrew Moss

Coax distribution system delivered to RAL Oct 13

• ALICE at Daresbury Laboratory operates using the Energy Recovery principle.

• Used as an R&D test facility for next generation electron beam technology development.

Booster

Compressor

IR-FEL

Photoinjector Laser

8 MeV

35 MeV

8 MeV

Accelerators and Lasers In Combined Experiments (ALICE)

24 http://www.stfc.ac.uk/ASTeC/Programmes/17425.aspx

Peter McIntosh

• International collaboration initiated in early 2006:– ASTeC (STFC)– Cornell University– DESY– FZD-Rossendorf– LBNL– Stanford University– TRIUMF

• Fabricate optimised ERL cryomodule and validate with beam.

• Dimensioned to fit on ALICE:– Same CM footprint– Same cryo/RF interconnects– ‘Plug Compatible’

New ALICE Cryomodule

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Peter McIntosh

Cryomodule EvolutionCavity

Tuner

Absorber

Integration

26Peter McIntosh

Cryomodule Reality

Cavity

Tuner

Absorber

Integration

27Peter McIntosh

Cryomodule Status

• Installed into ALICE in early 2013• RF & beam commissioning delayed by cryoplant

problems – unrelated to cryomodule!• RF Conditioning started 14th Nov• Both cavities have exceeded 10 MV/m, no

surprises so far, field emission low• So far, so good

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ALICE THz Exploitation

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IR/THz from ALICE

Tissue Culture Facility• CSR generated in THz Region as bunch length ~1 ps.

• Output enhanced by many orders of magnitude.

• Dedicated tissue culture laboratory.

• Effect of THz on living cells being studied.

• Source has very high peak intensities but very low average power:– no thermal effects!

Peter McIntosh/Peter Weightman

• Oesophageal cancer is the fastest rising cancer in the western world.

• Surgery is the only curative treatment but survival rates are poor because of late diagnosis.

• Challenge is to identify patients with oesophageal cancer much earlier.

Detection Signature:• Cancer cells surrounded by stroma made up of

various (non-cancer) cell types and ExtraCellular Matrix (ECM) proteins.

• Increase in number and change of morphology and architecture, relates to the function of the cancerous DNA molecules.

FEL Exploitation

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Cancerous Tissue

Non-Cancerous Tissue

• Scanning Near Field Optical Microscope (SNOM) is ideal probe

• Resolution:– Synchrotron (diffraction limited) 3 μm– ALICE Free Electron Laser (FEL) 0.1 μm

• Key is intensity and stability of the IR source.

ALICE will now be dedicated to cancer studies for 4 months per year

Peter McIntosh/Peter Weightman

• Uses ALICE as its injector• World’s first and only Non-

Scaling FFAG accelerator.• EMMA is an electron beam

demonstrator:– Verification of NS-FFAG beam

dynamics.

• First acceleration demonstrated in 2011

• Possible applications:– Muon beam acceleration– High intensity proton source for

ADSR energy production– Flexible source for proton and

carbon therapy

Electron Model for Many Applications (EMMA)

31 http://www.conform.ac.uk/Peter McIntosh

VELA (Versatile Electron Linear Accelerator)• High brightness RF Photoinjector at

Daresbury• Essential technology for advanced

electron facilities• Light sources• Colliders

• First RF Photoinjector in the UK• New tool for industry to develop new

accelerator-based technologies• Healthcare• Security scanners• Water treatment• ….

• Two independent beam areas available

• Funded August 2011• First Beam April 2013

Gun cavity and klystron provided by Strathclyde University/ALPHA-X

VELA

VELA Exploitation

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First Industrial Users on VELA (Sep 2013):• Rapiscan Systems (UK) and UCL spent 2 weeks exploiting

VELA’s ultra-short pulse properties to demonstrate a new time-of-flight imaging technique.

• This 3-year collaborative programme with STFC will potentially enable the next generation of cargo screening equipment.

Academic Users are also encouraged:• JAI will test new cavity BPMs in 2014• York/Swansea/UCL will carry out first electron diffraction commissioning

in 2014• CI/Strathclyde proposing plasma acceleration experiments (new laser

room with existing TW laser should be available Feb 2014)• Test of DLS 1 kHz RF photoinjector in 2014• New flexible end station for rapid turnaround of experiments being

designed now (enabling tests of dielectric structures, manipulation of phase space by THz, photonic structures, …)

CLARA (Compact Linear Accelerator for Research and Applications)

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• Free Electron Lasers– Ultra high peak intensity– Very short pulses of light– Tuneable– Basic FEL unstable in intensity and

wavelength– Immature as a technology, plenty of scope for

improvement– Fortunately lots of ideas exist for

improving FEL stability (wavelength and intensity) and to make even shorter pulses of light but very few have been tested

The CLARA Concept

There are many ways FELs can be improved, but limited scope with

existing facilities

UK Scientists need FELs and we want to develop next generation

FEL technology towards a possible UK facility

CLARACompact Linear Accelerator for Research and

Applications

An upgrade of the existing VELA Photoinjector Facility at Daresbury Laboratory to a Free-Electron Laser Test Facility

Proof-of-principle demonstrations of novel FEL concepts

Emphasis is ULTRA-SHORT PULSE GENERATIONNeil Thompson

CLARA Schematic

The existing VELA RF Photoinjector Facility

ELECTRONS

GENERATED

HERE

ELECTRONS ACCELERATED AND

MANIPULATED

INTERACTIONS

WITH LASER BEAMS

FEL OUTPUT GENERATED

FEL OUTPUT STUDIED

Neil Thompson

Example SchemesHere are two recent novel ideas, proposed by ASTeC and Strathclyde, which could be demonstrated in proof-of-principle experiments on CLARA

Mode-Locked AfterburnerA compact extension to an existing free-electron laser, which in the X-ray would produce Gigawatt pulses of only 700 zeptosecond duration, leapfrogging current demonstrated techniques by orders of magnitude

High-Brightness SASEA way of ‘slowing down’ the electron bunch in the free-electron laser to generate single wavelength X-ray pulses, without the need for a laser seed or any optics

Neil Thompson

Other Goals and Benefits of CLARA• The development of advanced technologies:

– New photoinjector technologies – Novel undulators (short period, cryogenic, superconducting….)– New accelerating structures– Single bunch diagnostics.

• The enhancement of VELA beam power and repetition rate, enabling additional industrial applications.

• The possibility to use the electron beam for other scientific research applications:

PLASMA ACCELERATOR

RESEARCH

ULTRAFA

ST ELECTRON

DIFFRACTIO

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COMPTON SCATTERIN

G

FOR GAMMA B

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DIELECTRIC

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ACCELERATION

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STORAGE RIN

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Neil Thompson

ALPHA-X

40 Mark Wiggins

41 Mark Wiggins

42 Mark Wiggins

43 Mark Wiggins

44 Mark Wiggins

Summary

• The UK operates two national accelerator facilities, Diamond and ISIS– Both have excellent performance and a vibrant user base– Both have major upgrade plans under development

• The UK has a number of test accelerators covering a broad remit– High power proton applications– Muon cooling demonstration– Light source/FEL motivated (based upon energy recovery, NC

Linac, & LPWA)– Industrial applications

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Thanks to everyone who provided material for this talk!

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