UK R&D Infrastructures and Accelerator Programmes Jim Clarke STFC Daresbury Laboratory TIARA-PP Final Meeting Daresbury Laboratory 25th November 2013

Outline National Accelerator Facilities Test Accelerators Summary Diamond Light Source ISIS Neutron Source Test Accelerators FETS MICE ALICE EMMA VELA CLARA ALPHA-X Summary

Diamond Light Source 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 at Rutherford Appleton Laboratory http://www.diamond.ac.uk/

Low-emittance beam mode Low-coupling mode: Micro-focusing Vertical coupling reduced from 1% to 0.3% during operations Low coupling  smaller source  smaller focused beam Compound Refractive Lenses CRLS – 18 lenses Photon Energy ~15 keV Source demagnification: 3.7m / 44m (~1/12) Knife edge scans using 200 µm Au wire CRL 44m 3.7m DCM B16-BM µ-focus E=15 keV Normal beam mode Low-emittance beam mode Focused beam size at sample reduced by 35%

Low-emittance beam mode Low-coupling mode: Nano-focusing Low coupling  smaller source  smaller focused beam FZP 47m 73mm DCM B16-BM n-focus E=8 keV 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 Normal beam mode Low-emittance beam mode Nano-focused beam (v) also reduced (from 144 nm to 124 nm)

Brilliance upgrade at Diamond Brilliance improvement for Diamond reduced coupling 1%  0.3% 300 mA  500 mA reducing diamond emittance with present hardware 2.7 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 Riccardo Bartolini

upgrade with Diamond-II (200pm): 300mA and 1%K Assuming the operation with a 200pm lattice Brilliance plot using U27 – 72 periods 2 m long with Kmax = 2.02 10 mm gap Tuning curves computed with Spectra 8.0 Riccardo Bartolini

doubling the number of beamlines while 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

Broken the 4 BA cell to leave 3 m space Modified 4BA cell Broken the 4 BA cell to leave 3 m space 12 quads per cell 10 Sextupoles per cell Straight section length slightly reduced 11 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 length Natural emittance Natural chromaticity : hor./ver. Straight length : long/short/middle 561.0 m 314.7pm-rad -146.7/-85.6 9.7/6.7/3 Gradient in bend < 15 T/m Quads gradient < 70 T/m Riccardo Bartolini

ISIS ISIS at Rutherford Appleton Laboratory Spallation neutron source based upon an 800 MeV proton synchrotron, enabling high quality science: Physics Chemistry Materials Science Earth Science Engineering Biology John Thomason http://www.isis.stfc.ac.uk/

ISIS Injection Upgrade New 180 MeV Linac ISIS Injection Upgrade 70 MeV Linac A New 180 MeV Injector Update old linac Increase beam power ~0.5 MW Advantages Reduces Space Charge (factor 2.6) Chopped, Optimised Injection & Trapping Challenges Injection straight Activation (180 MeV) Space charge, beam stability, .... MICE 800 MeV Synchrotron TS1 TS2 John Thomason

ISIS Injection Upgrade Ring Physics Study Snapshots of the work: challenges of getting 0.5 MW in the ISIS Ring Injection Longitudinal Dynamics Injection Straight Modelling Injection Straight Analytical Work Simulation Results Test Distribution Evolution of bunch Foil temperatures Injected distributions in (x,x’),(y,y’),(,dE) RF Bucket Variation of key parameters Transverse & Full Cycle 3D Dynamics Other Essentials: Activation, Diagnostics Predicted Space Charge Limit Single particle tune shift distributions at 0.5 MW Activation vs Energy Activation Measurements Coherent Tune Shift and Resonance Electron Cloud Monitor Strip-line Monitor/Kicker Accelerated distributions in (x,x’),(y,y’),(,dE) John Thomason

Ring High Intensity Beam Studies on ISIS John Thomason Ring High Intensity Beam Studies on ISIS Some of our R&D Studies Half-integer intensity limit in proton rings Using the ISIS ring to study halo formation New simulation code: Set 3Di Model losses, benchmark on ISIS Simulation Simulation Measurement (Y,Y) Y profile Y profile Higher order loss effects and images Investigating complex loss mechanisms Head-tail instability Key for high intensity proton rings Image driven resonance Vertical dipole motion along bunch on successive turns Vertical difference signal (along bunch, many turns) Loss vs Q measurement Samples along bunch Turn 

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

Front End Test Stand (FETS) 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 Radio Frequency Quadrupole Four-vane, 324 MHz, 3 MeV 4 metre bolted construction High power efficiency Diagnostics Non-interceptive Well distributed Laser-based Low Energy Beam Transport Three-solenoid configuration Space-charge neutralisation 5600 litre/s total pumping speed Medium Energy Beam Transport Re-buncher cavities and EM quads Novel ‘fast-slow’ perfect chopping Low emittance growth

FETS Ion Source R&D FETS applications include: 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)

FETS Low Energy Beam Transport FETS uses a 3 solenoid magnetic LEBT to match the beam from the ion source into the RFQ. Horizontal emittance 0.4 πmm.mRad rms norm Vertical emittance 0.3 πmm.mRad rms norm John 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

Muon Ionisation Cooling Experiment (MICE) 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. 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. http://mice.iit.edu/ John Thomason

MICE Hardware Development Tracker Focus Coil Absorber Cavity Module 200 MHz Cavity RF Be Window Coupling Coil John Thomason

RF power specification achieved at Daresbury Amplifier system has been dismantled from Daresbury and is currently being installed in the MICE hall Forward power into load

Coax distribution system delivered to RAL Oct 13

Accelerators and Lasers In Combined Experiments (ALICE) Compressor Photoinjector Laser 8 MeV IR-FEL Booster 35 MeV 8 MeV ALICE at Daresbury Laboratory operates using the Energy Recovery principle. Used as an R&D test facility for next generation electron beam technology development. Peter McIntosh http://www.stfc.ac.uk/ASTeC/Programmes/17425.aspx

Peter McIntosh New ALICE Cryomodule 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’

Cryomodule Evolution Absorber Cavity Tuner Integration Peter McIntosh

Cryomodule Reality Absorber Cavity Integration Tuner Peter 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

ALICE THz Exploitation 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! IR/THz from ALICE Peter McIntosh/Peter Weightman

Peter McIntosh/Peter Weightman FEL Exploitation Cancerous Tissue 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. 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

Electron Model for Many Applications (EMMA) 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 Peter McIntosh http://www.conform.ac.uk/

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 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) 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 CLARA Compact 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 GENERATION Neil Thompson

INTERACTIONS WITH LASER BEAMS CLARA Schematic FEL OUTPUT STUDIED FEL OUTPUT GENERATED The existing VELA RF Photoinjector Facility INTERACTIONS WITH LASER BEAMS ELECTRONS ACCELERATED AND MANIPULATED ELECTRONS GENERATED HERE Neil Thompson

Example Schemes Here are two recent novel ideas, proposed by ASTeC and Strathclyde, which could be demonstrated in proof-of-principle experiments on CLARA Mode-Locked Afterburner A 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 SASE A 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: COMPTON SCATTERING FOR GAMMA BEAMS PLASMA ACCELERATOR RESEARCH ULTRAFAST ELECTRON DIFFRACTION DIELECTRIC WAKEFIELD ACCELERATION NONEQUILIBRIUM STORAGE RINGS Neil Thompson

ALPHA-X Mark Wiggins

Mark Wiggins

Mark Wiggins

Mark Wiggins

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

Thanks to everyone who provided material for this talk!