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Welcome, ISIS overview, and core accelerator activities David Findlay Head, Accelerator Division ISIS Department Rutherford Appleton Laboratory / STFC Proton accelerator R&D at RAL, 24 March 2011. Welcome! Aim today: Outline description of proton accelerator R&D at RAL
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Welcome, ISIS overview, and core accelerator activities David Findlay Head, Accelerator Division ISIS Department Rutherford Appleton Laboratory / STFC Proton accelerator R&D at RAL, 24 March 2011
Welcome! • Aim today: • Outline description of proton accelerator R&D at RAL • Interest in contributing?
RAL • Spun off from UKAEA Harwell in late 1950s for nuclear and high-energy physics — PLA (50 MeV DTL, 1959–69), Nimrod (7 GeV synchrotron, 1964–78) • Then ISIS (1984– ) • UK proton accelerator R&D based at RAL because UK’s proton machines have been and are at RAL — knowledge, skills, experience, hardware, infrastructures • ASTeC Intense Beams Group + ISIS
ISIS Rutherford Appleton Laboratory, looking north-east
ISIS • Spallation neutron source + muons + MICE • First neutrons 1984 (TS-1), 2008 (TS-2) • World-leading in terms of science output • Structure and dynamics of molecules — physics, chemistry, materials science, geology, engineering and biology • 800 MeV protons on to tungsten targets, 0.2 MW • TS-1, 0.16 MW, 40 pps; TS-2, 0.04 MW, 10 pps • ~750 neutron experiments per year • ~1500 visitors/year (~5000 visits) • ~450 publications/year (~9000 total over 25 years) • UK: has largest neutron user community in the world
RFQ: 665 keV H–, 4-rod, 202 MHz Linac: 70 MeV H–, 25 mA, 202 MHz, 200 µs, 50 pps Synchrotron: 800 MeV proton, 50 Hz 5 µC each acceleration cycle Dual harmonic RF system Targets: W (Ta coated) Protons: 2 × ~100 ns pulses, ~300 ns apart Moderators: TS-1: 2 × H2O, 1 × liq. CH4, 1 × liq. H2 TS-2: 1 × liq. H2 / solid CH4, 1 × solid CH4 Instruments: TS-1: 20 TS-2: 7 (+ ChipIr, 14-Mar-11) ~300 staff
4-rod RFQ, 202 MHz0.2 MW RF pulsedtetrode One of four drift tube linac tanks, 202 MHz4 × 2 MW RF pulsedtriodes (tetrode drivers) RF systems at ISIS (1)
10 × Thales TH116 triodes 2 MW, 202 MHz RF amplifier RF systems at ISIS (2)
RF systems at ISIS (3) Ferrite-loaded RF cavity2.6–6.2 MHz (second harmonic)4 cavities on machine ~1 MW RF mean Ferrite-loaded RF cavity1.3–3.1 MHz (fundamental)6 cavities on synchrotron
High-power drives and anode power supplies RF systems at ISIS (4)
RF systems at ISIS — 6 324 MHz RFQ (FETS) 324 MHz 2 MW klystron
ISIS Cockcroft-Walton ... ... now at Cockcroft Institute
ISIS • An operational machine with a fixed timetable— has to run when the users want it to— problems need solving now • Complicated machine to run — needs knowledgeable and experienced accelerator staff to maintain operations sustainably [e.g. Dean Adams’ talk] • Staff cannot “just” run ISIS — they need to keep up with developments in the field, engage with similar people elsewhere, etc.
Accelerator R&D at ISIS [ASTeC work: Chris Prior’s talk] • Need knowledgeable and experienced accelerator staff to maintain ISIS operations sustainably1 • Need to enable accelerator staff to engage with similar staff elsewhere • Need to look forward to possible ISIS upgrades • Need to maintain RAL as UK centre for proton accelerator R&D • — first two not optional; R&D keeps good people • 1Big, complicated, expensive machines.
Accelerator R&D programmes at ISIS Front End Test Stand (FETS) [APL, DCF, JP]High-quality beams for high-power proton acceleratorsPrototype front end for upgraded ISISNot a paper accelerator — real equipment on groundEngineering and technician dimensionsStrong university involvement R&D for high-current rings [JWGT]Until recently, ISIS world’s highest average power RCSRare opportunity for measurements ISIS upgrade studies [JWGT]Enhanced capability for investigating structure and dynamics of molecular matter
Beam diagnostics and beam dump MEBT and beam chopper Laser profile measurement 324 MHz, 3 MeV, 4-vane RFQ 3-solenoid magnetic LEBT 65 keV, 60 mA, 2 ms, 50 Hz, H– ion source Front End Test Stand Ion source collaborations:CSNS, CERN, Culham, Oxford
R&D for high-current rings • Beam dynamics on high-current rings • Experimental measurements on ISIS ring — valuable and scarce resource • Code development and code bench-marking • Beam diagnostics development • RF systems development (DHRF, LOI) • Collaborations with ANL, J-PARC, KEK, Oxford, SNS
ISIS beam loss simulations using ORBIT Beam loss Time (ms) ORBIT simulations, 600k particles,64 CPUs, 3-D space charge Simulated beam loss: 9 % Measured beam Loss: 8 %
Beam diagnostics EC monitor 1 SP5 UPDATE PICTURE EC monitor 2 Electron cloud monitors Strip line beam position monitor to measure beam instabilities in ring Damping system?
ISIS upgrade studies • Phased upgrades • 0) Linac and TS-1 refurbishment • Linac upgrade for ~0.5 MW operations on TS-1 • ~3.3 GeV booster synchrotron — ~1 MW • 3) 800 MeV direct injection to booster — 2–5 MW • 800 MeV direct injection to booster + long pulse mode option • Overlap with neutrino factory
ISIS 180 MeV injection upgrade studies Injection of 4E13 protons at 180 MeV over 500 turns with painting in each plane under 3-D space charge (left) Foil studies show 6.3 foil re-circulations per proton raising temperature to 1500°K OPERA model of injection straight showing foil scatter product trajectories injection dipole magnets foil H− p H0 Foil hit distribution over injection
Key areas of expertise at ISIS Essentially: science and technology of proton accelerators with benefit of operational experience Optimal application of electrical, electronic, mechanical, RF and vacuum engineering Ability to calculate beam dynamics in detail— incl. benchmarking codes in standard andnon-standard states (e.g. coasting beams) Design and operation of beam diagnostics devices and interpretation of the signals arising from the devices
Key areas of expertise — cont’d Appreciation of the practical problems posed by high-power beam stops and collimators, induction of radioactivity in machine structures, etc. — including high-power targets State-of-the-art code development and hardware architecture for running the codes Assessment of the implications for ISIS of facilitating other R&D programmes such as MICE
Overall aims Run ISIS sustainably Prepare for ISIS upgrades Act as centre for proton accelerator R&D in UK1 Collaborate nationally and internationally 1E.g. build new proton machines in R8, R9, R80, ...