Transcript CCLRC Template - Science and Technology Facilities Council

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?
2
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
3
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
5
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
~300 staff
TS-2: 7 (+ ChipIr, 14-Mar-11)
7
View down north side of ISIS 70 MeV H– linac
Superperiods 9, 0 and 1 of the ISIS 800 MeV synchrotron
ISIS TS-1 experimental hall, 20 instruments
ISIS TS-2 experimental hall, 7 instruments (+1, 14 Mar.)
TS-1 tungsten target,
plates
TS-2 tungsten target, solid cylinder
4-rod RFQ, 202 MHz
0.2 MW RF pulsed
tetrode
One of four drift tube linac tanks, 202 MHz
4 × 2 MW RF pulsed
triodes (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 cavity
2.6–6.2 MHz (second harmonic)
4 cavities on machine
~1 MW RF mean
Ferrite-loaded RF cavity
1.3–3.1 MHz (fundamental)
6 cavities on synchrotron
High-power
drives and
anode
power
supplies
RF systems at ISIS (4)
RF systems at ISIS (5) — RF test facility (R79)
RF systems at ISIS — 6
324 MHz RFQ (FETS)
324 MHz 2 MW klystron
Ground-cutting for RAL
ISIS Cockcroft-Walton ...
... now at Cockcroft Institute
Men inside DTLs
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.
23
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
1 Big, complicated, expensive machines.
24
Accelerator R&D programmes at ISIS
Front End Test Stand (FETS) [APL, DCF, JP]
High-quality beams for high-power proton accelerators
Prototype front end for upgraded ISIS
Not a paper accelerator — real equipment on ground
Engineering and technician dimensions
Strong university involvement
R&D for high-current rings [JWGT]
Until recently, ISIS world’s highest average power RCS
Rare opportunity for measurements
ISIS upgrade studies [JWGT]
Enhanced capability for investigating structure and
dynamics of molecular matter
25
Front End Test Stand
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
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
27
ISIS beam loss simulations using ORBIT
Beam loss
6000
5000
4000
3000
2000
1000
0
-0.5
0
0.5
1
1.5
2
2.5
3
Time (ms)
3.5
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
1) Linac upgrade for ~0.5 MW operations on TS-1
2) ~3.3 GeV booster synchrotron — ~1 MW
3) 800 MeV direct injection to booster — 2–5 MW
4) 800 MeV direct injection to booster + long pulse
mode option
5) Overlap with neutrino factory
30
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
Foil hit
distribution
over
injection
H−
H0
p
Collaborations with CERN, Fermilab, Imperial
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 and
non-standard states (e.g. coasting beams)
Design and operation of beam diagnostics devices and
interpretation of the signals arising from the devices
34
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
35
Overall aims
Run ISIS sustainably
Prepare for ISIS upgrades
Act as centre for proton accelerator R&D in UK1
Collaborate nationally and internationally
1 E.g. build new proton machines in R8, R9, R80, ...
36
37