isis, fets and astec david findlay head, accelerator division isis department rutherford appleton...
TRANSCRIPT
ISIS, FETS and ASTeC
David FindlayHead, Accelerator DivisionISIS DepartmentRutherford Appleton Laboratory / STFC
ASTeC 10 Years On, Thursday 13 October 2011
ISIS, FETS, ASTeC (IBG),RAL
Electron-proton dipole
ASTeC, DL
Dipole moment ~1 C.m
~1030 Debye unitsElectric field at 1 m: ~10 GV/m
3
Overview of talk
ISISScience programmeAccelerator R&DUpgrades
Front End Test Stand
Rôle of ASTeC
4
But first — protons in the UK
At AERE1/Harwell/NIRNS2/RHEL/RAL:
Harwell synchrocyclotron (1949, 165 MeV, 1 µA)
PLA (Proton Linear Accelerator, 1959–1969)50 MeV, 3-tank — originally was to be 600 MeV
Harwell ~7 MV tandem accelerator
Harwell VEC (Variable Energy Cyclotron, 1965–1980s)
Nimrod, 7 GeV proton synchrotron (1964–1978)
ISIS, 800 MeV proton synchrotron (1984– )
1 Atomic Energy Research Establishment (1946)
2 National Institute for Research in Nuclear Science (1957)
Harwell tandem
PLA — Proton Linear Accelerator
Never built
Aimed down runway
PLA tank going into Building R12 at RAL
PLA tank in R5.1 — as part of new injector for Nimrod
Remedial work on other tanks for new injector for Nimrod
PLA tank in R5.1 — as part of injector for ISIS
Cockcroft at ground-breaking ceremony for Nimrod
Construction of Nimrod synchrotron hall
4.6 MVA alternator (+ 5100 HP motor + 24 ton flywheel) × 2
First beam from Nimrod
17
ISIS
World’s most productive spallation neutron source(if no longer highest beam power)
Flagship STFC facility [Sci. Tech. Facilities Council]
Driven by UK’s high-power proton accelerators
UK has largest national neutron user community of any country
Accelerator physics at ISIS necessary for continuing operations— and also for enabling entire programmes on materials R&D
Need to plan for upgrades
18
ISIS
Fundamental purpose — to investigate structure and dynamics of molecular matter
Neutron sources complement light sources
Neutrons: ~0.1 eV → ~1Å
Structure Atomic motionsParacetamol
Global challenges ISIS
Energy
Living with environmental change
Global threats to security
Ageing: Life-long health and wellbeing
Digital economy
Nanoscience: through engineering to application
Impact of ISIS science
ISIS from air
22
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 Hz5 µC each acceleration cycleDual harmonic RF system [Chris Prior]
Targets: 2 × 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 (+ 4 more now funded)
~340 staff
–35 kV H– ion source
665 keV 4-rod 202 MHz RFQ
70 MeV 202 MHz 4-tank H– linac
1.3–3.1 + 2.6–6.2 MHz 70–800 MeV proton synchrotron
Superperiods 9, 0 and 1 of 800 MeV synchrotron
EPB1 and EPB2 to TS-1 and TS-2 above synchrotron
Protons to TS-1
Protons to TS-2
ISIS TS-1 experimental hall, 20 instruments
ISIS TS-2 experimental hall, 7 instruments + 4 under way
TS-1 tungsten target, plates
TS-2 tungsten target, solid cylinder
ISIS Upgrades
4) Upgrade 3) + long pulse mode option
0) Linac and TS-1 refurbishment
1) Linac upgrade, ~0.5 MW on TS-1
2) ~3 GeV booster synchrotron: MW target
3) 800 MeV direct injection: 2–5 MW target
2) ~3 GeV RCS fed by bucket-to-bucket transfer from ISIS 800 MeV synchrotron (1MW, perhaps more)
3) Charge-exchange injection from 800 MeV linac (2 – 5 MW)
1) Replace 70 MeV ISIS linac by new ~180 MeV linac (~0.5 MW)
ISIS MW Upgrade Scenarios
ASTeC staff vital to success
• Based on MW ISIS upgrade with 800 MeV Linac and 3.2 GeV RCS
• Assumes a sharing of the beam
power at 3.2 GeV between the two facilities
• Both facilities can have the same ion source, RFQ, chopper, linac, H− injection, accumulation and acceleration to 3.2 GeV
• Requires additional RCS machine in order to meet the power and energy needs of the Neutrino Factory
Common proton driver for neutron source and neutrino factory
NF on Harwell Oxford site
muon linac
coolingphase rotationbunching
RLA 1
muonFFAG
RLA 2
decay ring to Norsaq155 m below ground
decay ring to INO440 m below ground
• UKAEA land now not to be decommissioned until at least 2040 (unless we pay for it!)
• Extensive geological survey data available, but needs work to interpret implications for deep excavation and ground water activation
37
FETS — Front End Test Stand
Actually the second front end test stand at RAL
First test stand was built to test RFQ to replace ISIS Cockcroft-Walton
ISIS 665 kV Cockcroft-Walton (1984–2004)
665 keV 4-rod 202 MHz RFQ
RFQ test standion source,
LEBT, RFQ, diagnostics
40
Front End Test Stand (FETS)
Key technology demonstrator for next generation of high power pulsed proton accelerators
ISIS upgrades
Neutrino factories
Future spallation neutron sources
Accelerator-driven systems
Waste transmutation
...
Only dedicated high-power proton accelerator hardware R&D project in the UK
41
Key components of FETS
High-intensity, high-duty factor, H– ion source(60 mA, 2 ms, 50 pps)
Magnetic low energy beam transport (LEBT)
324 MHz 4-vane RFQ
Medium energy beam transport (MEBT)
Very high speed beam chopper
Comprehensive beam diagnostics
Collaboration — ISIS, ASTeC, Imperial College, Warwick University, ESS Bilbao consortium, Royal Holloway,[Huddersfield, UCL]
In R8 at RAL
43
Ion source and LEBT optimisation
60 mA H– beam current demonstrated
Low measured emittance at high
current in the FETS LEBT
44
RFQ design + manufacture
RFQ cold model
Weld test models under
investigation at Imperial
Integrated electromagnetic, thermal, fluid flow and mechanical design
45
Beam chopper
Essential for all high-power proton accelerators with rings
FETS chopper
Two-stage for wide-band functionality
Basis for ESS design
464 metres
47
Helical prototype Planar prototype
Re-bunching cavities
48
Beam diagnostics
Already in use
Current transformers
Faraday cup
Slit-and-cup scanners for time-resolved 2D emittance
Scintillators for beam profiles
Pepper-pot for 4D phase space
Being developed
Laser photo-detachment(“laser wire”)
49
At present
Cutting metal for RFQ
Increasing laser power for laser wire
Continuing ion source development
…
In future
Commission RFQ
Demonstrate high-quality beam chopping
Spin out hands-on accelerator expertise
…
50
ASTeC
Re-packaging of long-held national lab. skills— larger package than in the past
Skills NINA, SRS, Nimrod, ISIS, Diamond, ...
“ASTeC” skills enabled / continue to enableNimrod ISISESS designs (1990s, early 2000s)ISIS second harmonic RF upgradeTS-2FETS
ISIS Accel. Theory Group ASTeC Intense Beams Group (IBG) — IBG still in ISIS R2 building
51
ASTeC — has enabled ISIS
Happy birthday!
And many happy returns!
— is enabling FETS
— will enable ISIS upgrades